Effects of Chronic Dietary Exposure to Phytoestrogen Genistein on Uterine Morphology in Mice.

Genistein is naturally occurring in plants and binds to estrogen receptors. Humans are mainly exposed through diet, but the use of supplements is increasing as genistein is claimed to promote health and alleviate menopausal symptoms. We analyzed diverse uterine features in adult mice chronically fed genistein for different times. The luminal epithelium height was increased in females treated with 500 and 1000 ppm at PND 95, and the width of the outer myometrium was increased in females treated with 1000 ppm at PND 65 compared to that in controls. An increase in proliferation was noted in the inner myometrium layer of animals exposed to 300 ppm genistein at PND 185 compared to that in controls. Luminal hyperplasia was greater in the 1000 ppm group at PND 65, 95, and 185, although not statistically different from control. These results indicate that genistein may exert estrogenic activity in the uterus, without persistent harm to the organ.

Di (2-ethylhexyl) phthalate (DEHP) alters proliferation and uterine gland numbers in the uteri of adult exposed mice.

Di-(2-ethylhexyl) phthalate (DEHP) is an endocrine-disrupting chemical that has been shown to impair normal reproductive function in males and females. This study investigated whether adult exposure to environmental and occupational doses of DEHP alters homeostasis of uterine proliferation, morphology, and number of uterine glands. Adult female CD1 mice were orally dosed with DEHP (0, 20 µg/kg/day, 200 µg/kg/day, 20 mg/kg/day or 200 mg/kg/day) for 30 days. Results indicated that DEHP at 200 µg/kg/day caused a reduction in epithelial cell proliferation in the uterus (p < .05). We also observed an increase (p < .05) in the number of uterine glands in mice dosed with 200 mg/kg/day DEHP. Results showed that DEHP caused an increase (p < .05) in dilated blood vessels in the endometrium at 200 µg/kg/day, 20 mg/kg/day and 200 mg/kg/day. DEHP also increased proliferation of endometrial stromal cells at 200 µg/kg/day DEHP (p < .0010), 20 mg/kg/day DEHP (p < .0001) and 200 mg/kg/day DEHP (p < .0186). Results suggest that, exposure to specific doses of DEHP for 30 days can have adverse effects on reproductive function.