The influence of phytoestrogens or estrogens on the proliferation of the rat endocervical mucosa

Abstract

SUMMARY INTRODUCTION Although estrogen therapy is widely used against post-menopausal symptoms, it can present adverse effects, including endometrial cancer. Soy isoflavones are considered a possible alternative to estrogen therapy. However, there are still concerns whether isoflavones exert trophic effects on the uterine cervix. OBJECTIVES To evaluate the histomorphometric and immunohistochemical alterations in the uterine cervix of ovariectomized rats treated with soy isoflavones (Iso). METHODS Fifteen adult Wistar rats were ovariectomized (Ovx) and divided into three groups: Group I (Ovx), administered with vehicle solution; Group II (OVX-Iso), administered with concentrated extract of Iso (150 mg/kg) by gavage; and Group III (OVX-E2), treated with 17β-estradiol (10 µg/kg), subcutaneously. After 30 days of treatments, the uterine cervix was fixed in 10% formaldehyde and processed for paraffin-embedding. Sections were stained with Hematoxylin and eosin for morphological and morphometric studies or subjected to immunohistochemistry for detections of Ki-67 and vascular endothelial growth factor-A (Vegf-A). The data obtained were subjected to statistical analysis (p ≤ 0.05). RESULTS We noted an atrophic uterine cervix in GI, whereas it was more voluminous in GII and even more voluminous in GIII. The thickness of the cervical mucosa was significantly higher in GIII, as compared to GI and GII. The cell proliferation (Ki-67) was significantly elevated in the estradiol and isoflavones treated groups, whereas Vegf-A immunoexpression was significantly higher in GIII, as compared to groups GII and GI. CONCLUSIONS Soy isoflavones cause less trophic and proliferative effects in the uterine cervix of rats as compared to estrogen.

EFECTO DE LOS FITOESTRÓGENOS DEL EXTRACTO ACUOSO DEL AGUAJE (Mauritia flexuosa L.) EN RATONES HEMBRA Mus musculus OVARIECTOMIZADAS

“…No obstante, es importante resaltar que en ninguno de los grupos estudiados se observó actividad estrogénica en términos del peso uterino, es decir, el peso uterino de las ratas tratadas con el extracto y el de las ratas ovariectomizadas que recibieron suero se mantuvieron en niveles similares. Además, en una investigación realizada por Franco et al (2020), se llevó a cabo una evaluación de los efectos de un extracto concentrado de isoflavonas de soja en el endocérvix de ratas Wistar que habían sido sometidas a ovariectomía. Los resultados de este estudio indicaron que las isoflavonas generaron efectos tróficos y proliferativos en el cuello uterino de las ratas, aunque en menor medida al compararse con los efectos observados con los estrógenos.…”

May isoflavones prevent breast cancer risk?

“…The extramammary benefits of soy are evident as in vasomotor symptoms 22 , skin 23 , bone mass 24 , and genital tract 25 .…”