Proliferation of the Superficial Epithelium of Ovaries in Senile Female Rats Following Oral Administration of Conjugated Equine Estrogens

Abstract

Perniconi SE, Simões MJ, Simões RS, Haidar MA, Baracat EC, Soares Junior JM. Proliferation of the superficial epithelium of ovaries in senile female rats following oral administration of conjugated equine estrogens. Clinics. 2008;63:381-8. OBJECTIVE:To evaluate the effect of different concentrations of estrogen on the ovarian superficial epithelium in senile female rats. Design: Fifty female rats at 15 months of age and with irregular estrous cycles were selected and randomly divided into five experimental groups containing equal numbers of animals in each: GPROP, control group receiving vehicle only; GE0.05mg, group receiving conjugated equine estrogens (CEE) at a dose of 50 µg/kg; GE0.5mg, group receiving CEE at 500 µg/kg; GE1mg, group receiving CEE at 1 mg/kg; and GE2mg, receiving CEE at 2 mg/kg. The length of treatment was 21 days. After this period, the animals were anesthetized and the ovaries were fixed in 10% formaldehyde and processed for routine histology. Histomorphology was analyzed by light microscopy, and histomorphometrics were evaluated using the Imagelab program. RESULTS: In the GPROP and GE0.05mg groups, the superficial epithelium of the ovary had a simple cuboidal shape, and as the estrogen dose increased, the epithelium thickened, with pseudo-stratified or stratified epithelium appearing in the GE2mg group. The animals in the group given the highest estrogen dose (GE2mg) showed the thickest ovarian epithelium and the largest perimeter and surface area of the surface ovarian epithelium (P < 0.01). However, the difference in epithelium thickness between the GE0.5mg and GE1mg groups was only slight. CONCLUSION: Our data suggest that CEE at a dose of 2 mg/kg may induce marked proliferation of rat ovarian epithelium.

Microscopic Evaluation of Ovarian Surface Epithelium Following Treatment with Conjugated Estrogens in a Mouse Model

“…OSE exhibited an increase in the multilayers of squamous epithelium. Similar findings also reported in other studies (Perniconi et al, 2008;Vuong et al, 2017). Epithelial cells exhibit contact behavior for proper formation of the epithelial monolayer by inhibiting cell proliferation upon contact with neighboring cells.…”

Prenatal and pubertal exposure to 17α-ethinylestradiol disrupts folliculogenesis and promotes morphophysiological changes in ovaries of old gerbils (Meriones unguiculatus)

“…82,83 Previous studies showed that the administration of high doses of estrogen promoted the excessive proliferation of ovarian epithelium of 12-month-old female rats. 84 Our study reinforces that low doses of ethinylestradiol may lead to thickening of ovarian epithelium. Thus, other studies should be developed to evaluate the effects of low doses of estrogen during prenatal and puberty in the risk of ovarian cancer and other proliferative disorders.…”

Highlighting early detection of thyroid pathology and gestational diabetes effects on oxidative stress that provokes preterm delivery in thyroidology: Does that ring a bell?

“… 18 As the prevalence of the various risk factors for GDM, among which is polycystic ovarian syndrome, is rising worldwide 19 , there is necessary to anticipate the possible complications among these patients. The authors have not noticed any other morbidity risk as family malignant potential 20 , 21 , 22 or rather a frequent pathology in women as endometriosis. 23 , 24 , 25…”