Uterus Of Ovariectomized Rats Research Articles

Effects of soy isoflavones extract on the lipid profile and uterus in ovariectomized rats

Aim Although soy isoflavones (ISO) have been shown to relief postmenopausal symptoms, it remains inconclusive whether ISO can improve lipid-profile without uterotrophic effects under estrogen-deficiency. Thus, we investigated the effects of ISO on lipid-profile and uterus of ovariectomized (Ovx) rats. Materials and methods Twenty-five adult rats were Ovx or Sham-operated (Sham) and assigned into five groups: Sham and Ovx groups, administered with vehicle solutions; Ovx-E, treated with 10 µg/kg of 17β-Estradiol; Ovx-ISO, treated with 200 mg/kg of ISO; Ovx-E + ISO, treated with estradiol + ISO combined. After fifty days of treatments, rats were euthanized and uterine horns were processed for histomorphometry or to collagen fibers and glycosaminoglycans evaluations. Blood samples were collected to evaluate levels of triglycerides, total cholesterol (TC) and its fractions (HDL/VLDL). Data were subjected to statistical analysis (p < .05). Results Uterus weight was lower in Ovx group than the Sham and Ovx-E groups, whereas it was similar between Ovx and Ovx-ISO groups. Histomorphometry showed atrophic uterus in Ovx and Ovx-ISO groups, whereas uterotrophic effects were noticed in Ovx-E and Ovx-E + ISO groups. Collagen fibers-birefringence was higher in Sham, Ovx, and Ovx-ISO groups than in Ovx-E and Ovx-E + ISO groups. Sulfated glycosaminoglycans content was similar among Sham, Ovx, and Ovx-ISO groups, while it was higher in estrogen-treated groups; total glycosaminoglycans content was similar among groups. TC and HDL was higher in Ovx-ISO group, whereas VLDL and triglycerides levels was higher in Ovx-E + ISO group and similar among other groups. Conclusion Soy isoflavones at 200 mg/kg have slight beneficial effects on lipid-profile without uterotrophic effects in Ovx rats.

SAT-196 Maternal immunity: Preimplantation Preparation

The maternal uterus in mammals undergoes extensive remodeling in preparation for implantation of the semi-allogeneic embryo. Activation of the T cell homing receptor, CCR7, regulates multiple aspects of adaptive immunity. Genetic deletion of CCR7 reduces T regulatory (Treg) cell migration into mouse uteri and decreases embryo implantation. CCL19 and CCL21 are the sole ligands for CCR7. We hypothesized that CCL19 and/or CCL21 expression could attract Treg cells into the pre-implantation uterus and provide local immune suppression prior to implantation. Sprague Dawley rat uteri were removed from pregnant rats at Days 3-6. RNA was isolated and real time PCR was used to measure CCL19 and CCL21 expression. To determine the spatial distribution of these ligands, rat uteri were fixed, embedded in paraffin and uterine sections were analyzed by immunocytochemistry. The influence of sex steroids on the spatial distribution of CCL19 was evaluated in uterine sections from steroid treated rats. Hormonal control of CCL19 and CCL21 expression was investigated in a rat uterine stromal cell line treated with female sex steroids. Expression of CCL19 and CCL21 peaked at Day 4 of pregnancy compared with Days 3, 5 or 6 (Mann Whitney, p <0.05). Interestingly, expression of both ligands was significantly higher (p < 0.05) in the inter-site regions compared with the implantation sites at Day 6 of pregnancy. At Day 3 of pregnancy, CCL21 expression was limited to the glandular epithelium. Expression appeared in the antimesometrial uterine stroma at Day 4 of pregnancy. The distribution of CCL21 was similar between Days 4 and 5 of pregnancy but expression was less robust at Day 5. CCL21 expression was lost from the glands at Day 6 but was maintained in the antimesometrial stroma of the inter-site regions. CCL19 was expressed in the luminal and glandular epithelia of ovariectomized rat uteri. Progesterone pretreatment (2 mg daily, 3 days) stimulated expression of CCL19 in the periluminal stroma, which extended into the antimesometrial regions. Estradiol (0.2 µg) administration to progesterone pretreated rats, increased the expression of CCL19 but did not change its spatial distribution. Both ligands were detected in a rat uterine stromal cell line. CCL19 expression increased in response to estradiol (10 nM) at 6 h after hormone addition. Taken together, these results suggest that the maternal preparation for implantation includes a peak in the expression of CCL19 and CCL21 at Day 4 of pregnancy, one day prior to implantation in the rat. Unlike the constitutive expression of these ligands in primary and secondary lymphoid tissue, the spatial distribution and expression of CCL19 and CCL21 is regulated by female sex steroids in the uterus. The data support the concept that immune-mediated events, necessary for successful implantation and pregnancy, are induced in females prior to implantation. Funded by NIH.

Hormone-like activities of Kuntai capsule in the uteri of ovariectomized rats and immature rabbits

OBJECTIVETo investigate the hormone-like activities of Kuntai capsule (KTC) in the uteri of ovariectomized rats and immature rabbits. METHODSFollowing bilateral ovariectomy, rats were randomly divided into six groups including sham group, control group, estradiol valerate group, KTC 0.24, 0.6, and 1.5 g/kg groups. The rats were treated with 0.5% CMC-Na, estradiol valerate and KTC (0.24, 0.6, and 1.5 g/kg), respectively for 28 consecutive days. Then the estrous cycle, uterine changes and pathological changes were examined. Serum levels of estradiol (E2), and progesterone (P4) were measured by enzyme-linked immunosorbent assay (ELISA). Protein levels of estradiol receptor (ER), progesterone receptor (PR), vascular endothelial growth factor (VEGF), proliferating cell nuclear antigen (PCNA) and nuclear-associated antigen-67 (Ki-67) in uterine tissues were detected by western blot. Immature rabbits were estrogen-primed prior to intragastric administration with KTC for 6 d consecutively. Then, the uteri underwent hematoxylin-eosin staining to observe endometrial transformation. RESULTSCompared with the control group, 0.6 and 1.5 g/kg KTC markedly decreased the uterine organ coefficient and endometrial thickness (P < 0.05). The serum level of P4 was increased in the KTC 0.6 g/kg group (P < 0.05). There were no significant variations in the serum level of E2 in the KTC groups compared with the control group. ERβ, but not ERα, was markedly upregulated after KTC administration (P < 0.05). Furthermore, 1.5 g/kg KTC significantly decreased the protein level of PRA (P < 0.05) and 0.6 g/kg KTC increased the protein level of PRB in the uteri (P < 0.05). VEGF was highly expressed after treatment with 0.24 and 0.6 g/kg KTC, and Ki-67 was markedly reduced in ovariectomized rats treated with 1.5 g/kg KTC. No difference was found in the expression of PCNA. KTC 0.24 and 0.6 g/kg promoted endometrial transformation in immature rabbit uteri. CONCLUSIONKTC does not demonstrate obvious estrogen-like effect on uteri after ovariectomy, but it does exhibit weak progestogen-like effect, by which mechanism of action is yet to be further investigated.

The effects of bortezomib on the ovariectomy applied rat uterus: A histopathological, stereological, and immunohistochemical study.

Objective(s):In this study, potential protective effects of Bortezomib (Bort), as a proteasome inhibitor, were investigated on the uterus of ovariectomized rats by histological, morphometric and immunohistochemical methods.Materials and Methods:In this study, 18 Sprague dawley strain female rats (12 weeks old, 250-300 g body weight) were used. Animals in the control group (Cont, n=6) were not exposed to any treatment. Ovariectomy was performed on the experimental groups. They (n=12) were divided into ovariectomy (Ovt, n=6) and Bortezomib (Bort, n=6) subgroups. Twelve weeks later, the rats were perfused. Then, uterine tissues were removed and examined by morphometrical, and light and electron microscopy methods. In addition, immunoreactivity of nuclear factor-kappa (NF-κB) was evaluated.Results:Morphometric and histopathological evaluations showed that Bort was effective in the uterus and protects the layer structures and the cells.Conclusion:In the light of these findings, we suggest that for proteasome inhibitor particularly Bort is thought to be useful through proteasome inhibition and NF-κB pathway.

Effects of the aryl hydrocarbon receptor agonist 3-methylcholanthrene on the 17β-estradiol regulated mRNA transcriptome of the rat uterus

Polycyclic aromatic hydrocarbons (PAHs) are products of incomplete combustion of organic compounds, abundant in exhaust fumes and cigarette smoke. They act by binding to the aryl hydrocarbon receptor (AHR) which induces expression of phase 1 and phase 2 enzymes in the liver. PAH induced AHR activation may also lead to adverse effects by modulating other pathways, for example estrogen receptor (ER) signaling in the female reproductive tract. We have investigated the effects of the PAH 3-methylcholanthrene (3-MC) on 17β-estradiol (E2) dependent signaling in the uterus of ovariectomized rats to characterize the cross talk between AHR and ER on an mRNA transcriptome wide scale. A standard three day uterotrophic assay was performed in young adult Lewis rats. Treatment induced effects were analyzed using histology, immunohistochemistry and gene expression analysis by microarray and qPCR. 3-MC shows broad E2 antagonistic effects on uterine mRNA transcription of the vast majority of E2 regulated genes, significantly altering prostaglandin biosynthesis, complement activation, coagulation pathways and other inflammatory response pathways. The regulation of ER expression in the uterus, but not the regulation of E2 metabolism in the liver, was identified as a potentially important factor in mediating this general antiestrogenic effect. The regulation of prostaglandin biosynthesis by E2 is important for inflammation-like events during pregnancy including the initiation of birth. Our results suggest that adverse effects of PAHs on prostaglandin related pathways are likely caused by the interference with E2 signaling, specifically by inhibiting the E2 mediated downregulation of PGF2α. Characterization of the generalized antagonistic effect of 3-MC on E2 dependent signaling in the rat uterus thus contributes to a better understanding of molecular mechanisms of the toxicity of PAHs in female reproductive organs.

The protective effect of the proteasome inhibitor bortezomib on the uterus of ovariectomized rats

Bortezomib (BORT) is an anti-tumour agent that inhibits proteasome, which is responsible for the degradation of many intracellular proteins. Although some side-effects and chemotherapeutic effects of BORT are known, there has not been enough research regarding its effects on different tissues of proteasome inhibition in the senile period (post-menopausal). The aim of this study was to investigate the safety of using BORT during the post-menopausal period. The post-menopausal effects of BORT were investigated on ovariectomized (OVX) Spraque-Dawley rats. The female rats were separated into three groups: control, ovariectomized (OVX), and OVX + BORT. OVX and OVX + BORT groups consisted of six rats in each. BORT was administered intraperitoneally in a dosage of 0.2 mg/kg two days a week for four weeks after OVX. The uteri of the rats were investigated using morphometrical, histopathological, and immunohistopathological methods. A striking atrophy in the endometrium and myometrium was observed due to an estrogen deficiency in the OVX group. The partial protective effect of BORT administration was observed morphometrically and histopathologically. In immunohistochemical research, cytoplasmic NF-&#x03BA;B activity was observed in the presence of proteasome inhibition in the endometrium. In light of these findings, the limited protective effects of post-menopausal BORT administration are worth mentioning.

Effects of a glyphosate-based herbicide on the uterus of adult ovariectomized rats.

Glyphosate is the active ingredient of several herbicide formulations. Different reports suggest that glyphosate-based herbicides (GBHs) may act as endocrine disruptors. We evaluated the potential estrogenic effects of a GBH formulation using the uterotrophic assay. Adult ovariectomized rats were sc injected for 3 consecutive days with: saline solution (vehicle control), 2.10-5 g E2 /kg/day (uterotrophic dose; UE2 ), 2.10-7 g E2 /kg/day (nonuterotrophic dose; NUE2 ), or 0.5, 5, or 50mg GBH/kg/day of the. Twenty-four hours after the last injection, the uterus was removed and weighed and processed for histopathology and mRNA extraction. Epithelial cell proliferation and height and expression of estrogen-responsive genes were evaluated (estrogen receptors, ERα and ERβ; progesterone receptor, PR; complement 3, C3). Uterine weight and epithelial proliferation were not affected by GBH. However, the luminal epithelial cell height increased at GBH0.5. ERα mRNA was downregulated by all GBH doses and E2 groups, whereas PR and C3 mRNA were diminished by GBH0.5. GBH5-, GBH50-, and UE2 -treated rats showed downregulated ERα protein expression in luminal epithelial cells, while the receptor was upregulated in the stroma. GBH upregulated ERβ (GBH0.5-50) and PR (GBH5) expressions in glandular epithelial cells, similar effect to that of NUE2 group. These results indicate that, although the uterine weight was not affected, GBH modulates the expression of estrogen-sensitive genes. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 1191-1201, 2017.

In vivo xenoestrogenic actions of cadmium and arsenic in anterior pituitary and uterus.

Cadmium (Cd) and arsenic (iAs) are toxic metals ubiquitously present in the environment. Both pollutants exert nonmonotonic dose responses, being mostly cytotoxic at high concentrations but mimicking estrogen (E2) effects at low doses. Xenoestrogenic activity of Cd and iAs has been demonstrated in different hormone-dependent tumor cell lines; however, their actions in vivo remain largely unknown. Here, we investigated whether in vivo administration of low doses of Cd and iAs through drinking water would display xenoestrogenic effects in the anterior pituitary gland and uterus of ovariectomized rats. Cd (1ppm) and iAs (0.1ppm) exposure increased the wet weight of anterior pituitary gland and uterus and induced proestrus- and estrus-like vaginal smears. Both metals stimulate cell proliferation of these tissues as they increased the expression of proliferation markers. More importantly, they augmented soluble guanylyl cyclase α1 subunit expression, which has been linked to hormone-dependent tumor progression. Also, Cd and iAs modified protein levels of full-length estrogen receptor α and its truncated variants in an E2-like manner. Anterior pituitary hormone secretion was differentially affected by both metals. Luteinizing hormone synthesis and release were strongly diminished after Cd exposure and only mildly reduced by iAs. Both metals were able to increase prolactin synthesis, although only iAs augmented serum prolactin levels. This study shows for the first time that Cd and iAs exert strong xenoestrogenic effects on anterior pituitary gland at low doses. The differences between Cd and iAs E2-like behavior indicate that other Cd- and iAs-specific mechanisms could be involved. Altogether, these results contribute to the knowledge of reproductive disorders associated with Cd and iAs environmental contamination.

Olive oil exhibits osteoprotection in ovariectomized rats without estrogenic effects.

The present study was designed to evaluate the effect of olive oil on bone and uterus in ovariectomized rats. A total of 34 surgically ovariectomized or sham-operated virgin Sprague-Dawley rats were divided into four groups: i) Sham-operated control rats (sham group); ii) Ovariectomized rats (OVX group); iii) Olive oil-supplemented ovariectomized rats (olive group); and iv) Diethylstilbestrol-supplemented ovariectomized rats (E2 group). At 12 weeks following left ventricular blood sacrificed to detect plasma estradiol (E2), interleukin-1β (IL-1β) and IL-6 levels. Bone mineral density (BMD) of the lumbar spine was evaluated using dual-energy X-ray absorptiometry, and the left femur proximal 1/3 slices were observed using transmission electron microscopy. Uterine wet weight and the uterus index (ratio of uterine wet weight and body weight) were compared, and the uterine endometrium was observed using a light microscope. In the OVX group, serum E2 was significantly lower and IL-1β and IL-6 levels were significantly higher compared with the sham group. By contrast, serum E2 levels increased and IL-1β levels decreased in the olive group, but showed no significant difference compared with the sham group. The lumbar spine BMD in the olive group was increased compared with OVX group. Electron microscopy revealed sparse collagen fibers in the OVX group, with decreased density and multi-cavity, showing pathological features of osteoporosis. By contrast, the situation was improved in the E2 and olive groups, in which organelles such as the rough endoplasmic reticulum, mitochondria and Golgi apparatus were visible and active. Compared with the sham group rats, the uterine wet weight and uterine index decreased in the OVX and olive groups; however, no statistically significant difference was observed in the E2 group. Furthermore, endometrial hyperplasia was not observed in the olive group, which were apparently different from E2 group. The present results suggest that olive oil can effectively reduce bone loss in ovariectomized rats, and with no or only mild effects on the uterine endothelium.

Estrogen and progesterone differentially regulate carbonic anhydrase II, III, IX, XII, and XIII in ovariectomized rat uteri

Changes in the uterus expression of carbonic anhydrase (CA) II, III, IX, XII, and XIII were investigated under the influence of sex-steroids in order to elucidate mechanisms underlying differential effects of these hormones on uterine pH. Uteri of ovariectomised rats receiving over three days either vehicle, estrogen, or progesterone or three days estrogen followed by three days either vehicle or progesterone were harvested. Messenger RNA (mRNA) and protein levels were quantified by real-time PCR and Western blotting, respectively. The distribution of CA isoenzymes proteins were examined by immunohistochemistry. The levels of CAII, III, XII, and XIII mRNAs and proteins were elevated while levels of CAIX mRNA and protein were reduced following progesterone-only and estrogen plus progesterone treatment, compared to the control and estrogen plus vehicle, respectively. Following estrogen treatment, expression of CAII, IX, XII, and CAXIII mRNAs and proteins were reduced, but remained at a level higher than control, except for CAIX, where its level was higher than the control and following progesterone treatment. Under progesterone-only and estrogen plus progesterone influences, high levels of CAII, III, XII, and XIII were observed in uterine lumenal and glandular epithelia and myometrium. However, a high level of CAIX was observed only under the influence of estrogen at the similar locations. In conclusion, high expression of CAII, III, XII, and XIII under the influence of progesterone and estrogen plus progesterone could result in the reduction of uterine tissue and fluid pH; however, the significance of high levels of CAIX expression under the influence of estrogen remains unclear.

Ferutinin dose-dependent effects on uterus and mammary gland in ovariectomized rats.

The present paper completes our recent study on the effects of phytoestrogen ferutinin in preventing osteoporosis and demonstrating the superior osteoprotective effect of a 2 mg/kg/day dose in ovariectomized (OVX) rats, compared to both estrogens and lower (0.5, 1 mg/kg/day) ferutinin doses. Morphological and morphometrical analyses were performed on the effects of different doses of ferutinin administrated for one month on uterus and on mammary gland of Sprague-Dawley OVX rats, evaluated in comparison with the results for estradiol benzoate. To verify whether ferutinin provides protection against uterine and breast cancer, estimations were made of both the amount of cell proliferation (by Ki-67), and the occurrence of apoptosis (by TUNEL), two processes that in unbalanced ratio form the basis for cancer onset. The results suggest that the effects of ferutinin are dose dependent and that a 2 mg/kg/day dose might offer a better protective action against the onset of both breast and uterine carcinoma compared to ferutinin in lower doses or estradiol benzoate, increasing cellular apoptosis in glandular epithelia.

Functions of Danggui Buxue Tang, a Chinese Herbal Decoction Containing Astragali Radix and Angelicae Sinensis Radix, in Uterus and Liver are Both Estrogen Receptor-Dependent and -Independent.

Danggui Buxue Tang (DBT), a herbal decoction containing Astragali Radix (AR) and Angelicae Sinensis Radix (ASR), has been used in treating menopausal irregularity in women for more than 800 years in China. Pharmacological results showed that DBT exhibited significant estrogenic properties in vitro, which therefore suggested that DBT could activate the nuclear estrogen receptors. Here, we assessed the estrogenic properties of DBT in an ovariectomized in vivo rat model: DBT was applied to the ovariectomized rats for 3 days. The application of DBT did not alter the weight of uterus and liver, as well as the transcript expression of the proliferation markers including the estrogen receptors α and β. However, DBT stimulated the transcript expression of the estrogen responsive genes. In addition, the inductive role of DBT on the expression of members of the aryl hydrocarbon receptor family in uterus and liver of ovariectomized rats was confirmed. These responses of DBT however were clearly distinct from the response pattern detectable here for 17β-estradiol. Therefore, DBT exhibited weak, but significant, estrogenic properties in vivo; however, some of its activities were independent of the estrogen receptor. Thus, DBT could be an exciting Chinese herbal decoction for an alternative treatment of hormone replacement therapy for women in menopause without subsequent estrogenic side effects.

Kaempferol Exhibits Progestogenic Effects in Ovariectomized Rats.

Progesterone (P4) plays a central role in women's health. Synthetic progestins are used clinically in hormone replacement therapy (HRT), oral contraceptives, and for the treatment of endometriosis and infertility. Unfortunately, synthetic progestins are associated with side effects, including cardiovascular disease and breast cancer. Botanical dietary supplements are widely consumed for the alleviation of a variety of gynecological issues, but very few studies have characterized natural compounds in terms of their ability to bind to and activate progesterone receptors (PR). Kaempferol is a flavonoid that functions as a non-steroidal selective progesterone receptor modulator (SPRM) in vitro. This study investigated the molecular and physiological effects of kaempferol in the ovariectomized rat uteri. Since genistein is a phytoestrogen that was previously demonstrated to increase uterine weight and proliferation, the ability of kaempferol to block genistein action in the uterus was investigated. Analyses of proliferation, steroid receptor expression, and induction of well-established PR-regulated targets Areg and Hand2 were completed using histological analysis and qPCR gene induction experiments. In addition, kaempferol in silico binding analysis was completed for PR. The activation of estrogen and androgen receptor signalling was determined in vitro. Molecular docking analysis confirmed that kaempferol adopts poses that are consistent with occupying the ligand-binding pocket of PRA. Kaempferol induced expression of PR regulated transcriptional targets in the ovariectomized rat uteri, including Hand2 and Areg. Consistent with progesterone-l ke activity, kaempferol attenuated genistein-induced uterine luminal epithelial proliferation without increasing uterine weight. Kaempferol signalled without down regulating PR expression in vitro and in vivo and without activating estrogen and androgen receptors. Taken together, these data suggest that kaempferol is a unique natural PR modulator that activates PR signaling in vitro and in vivo without triggering PR degradation.

Glycosaminoglycan profiles in the uterus of adult ovariectomized rats treated with estrogen and progestagen

To evaluate the effects of conjugated equine estrogens (CE) alone or in combination with medroxyprogesterone acetate (MPA) on glycosaminoglycans (GAGs) in the cervix and horns of the rat uterus. Thirty days after ovariectomy, adult rats were randomly divided into four groups: GI, control (treated with drug vehicle); GII, CE (50 μg/kg per day); GIII, MPA (0.2mg/kg per day), and GIV, CE+MPA (doses as in GII and GIII). Drugs and vehicle were given by gavage during 28 days. Afterwards the animals were anesthetized, the cervix and uterine horns were dissected out and the middle portion fixed in 10% formaldehyde solution; other portions were fixed in acetone for histological examination and glycosaminoglycan quantification, respectively. Agarose gel electrophoresis was used for sulfated GAG analyses, and hyaluronic acid was assayed with an ELISA-like method. Statistical analysis was done by the Student's t test and the Tukey-Kramer test (P<0.05). The cervix and uterine horn structures presented signs of atrophy in the control group (GI). The other groups, mainly groups III and IV, had histological aspects of proliferation. In all groups the concentration of sulfated GAGs (especially dermatan sulfate) was higher than that of non-sulfated GAGs, both in cervix and in uterine horns. Estrogens increased sulfated GAG concentration at the cervix and the horn, whereas in uterine horns the amounts of sulfated GAGs were decreased after estrogens plus MPA treatment. The concentration of hyaluronic acid in uterine horns was higher than in cervices. The profiling and amounts of glycosaminoglycans in the two portions of the rat uterus are uneven. Dermatan sulfate occurs in higher concentrations in both cervix and uterine horns. Sulfated GAGs in rat cervix were increased by estrogens plus MPA, but were decreased by MPA alone in uterine horns.

Tissue specific localization of angiotensin-(1–7) and its receptor Mas in the uterus of ovariectomized rats

The vasoactive peptide angiotensin (Ang)-(1-7) has vasodilator, antifibrotic and antihypertrophic properties, but little is known about its regulation in the uterus. The aim of this study was to evaluate Ang-(1-7) and its receptor Mas expression throughout rat uterine tissues, in ovariectomized animals treated with estrogen alone or combined with progestin. Adult Wistar rats (n = 19) were ovariectomized and randomly assigned into three different groups 1 week later. One group received a single dose of estradiol benzoate (1.5 mg/kg, i.m. injection, n = 6). Another group received estradiol associated with depot medroxyprogesterone acetate (3 mg/kg, i.m. injection, n = 6). Control group (n = 7) received oil injection. One week later, the rats were euthanized and their uteri were fixed and stained by immunohistochemistry, using a polyclonal antibody specific to Ang-(1-7) and its receptor Mas. Ang-(1-7) was detected in all uterine tissues, but it was weak or absent in the circular myometrium of treated animals. The intensity of the immunostaining decreased in the glandular epithelium of hormonally treated animals when compared to controls. In estrogen treated rats, Ang-(1-7) labeling was scattered and sometimes included the nuclei of glandular cells. We also detected Ang-(1-7) expression in longitudinal myometrium and uterine serosa. Mas receptor was present in all tissues with similar intensity among the tissue types in the control and estrogen plus progestin groups. In the estrogen group, Mas staining was stronger in the luminal and glandular epithelium when compared with stroma or circular myometrium. In conclusion, ovarian steroids are not required to allow endometrial expression of Ang-(1-7) and its receptor Mas in rats, as it remains abundant in ovariectomized animals. However, estrogen and progestin may modulate the distribution pattern of this peptide in the endometrium, especially in the glandular compartment.

Hormonally Active Doses of Isoflavone Aglycones Promote Mammary and Endometrial Carcinogenesis and Alter the Molecular Tumor Environment in Donryu Rats

Our research is focused on modifying effects of an isoflavone aglycones (IAs)-rich extract at a hormonally active dose of 150 mg/kg body weight/day on mammary and endometrial carcinogenesis in female Donryu rats. IA administered for 2 weeks in a phytoestrogen-low diet exerted estrogenic activity and induced cell proliferation in the uterus of ovariectomized rats. Furthermore, administration for 4 weeks resulted in elevation of cell proliferation in the mammary glands of 7,12-dimethylbenz[a]anthracene (DMBA)-treated animals. Forty weeks of postpubertal administration of IA to 5-week-old rats after initiation of mammary and endometrial carcinogenesis with DMBA and N-ethyl-N'-nitro-N-nitrosoguanidine (ENNG) caused significant increase of incidence and multiplicity of mammary adenocarcinoma, multiplicities of endometrial atypical hyperplasia, adenomatous polyps, and an increased trend of uterine adenocarcinomas. Liquid chromatography with tandem mass spectrometry and immunohistochemical analyses revealed significant elevation of tumorigenesis-related proteins such as S100 calcium-binding protein A8, kininogen 1, and annexins 1 and 2 in mammary adenocarcinomas and cadherin EGF LAG seven-pass G-type receptor 2, DEAD box polypeptide 1, and cysteine- and glycine-rich protein 1 in uterine proliferative lesions of IA-treated animals. Those changes are likely to be related to modulation of estrogen receptor (ER), AP1, nuclear factor-kappa B, and actin signaling pathways. Our results indicate that the postpubertal exposure of Donryu rats to IA at an estrogenic dose results in promotion of mammary and uterine carcinogenesis induced by DMBA and ENNG, which might be related to the activation of ER-dependent signaling and alteration of the molecular tumor environment in the mammary gland and endometrium.

Effects of selective estrogen receptor agonists on estrogen receptor expression in the uterus of ovariectomized rats

The aim of the present study was to investigate effects of short time treatment with estrogen receptor (ER) selective agonists on ERα, ERβ and G-protein coupled estrogen receptor-1 (GPER) expression in the uterus of ovariectomized rats. The rats were treated with either estradiol (E2), the specific ERα agonist PPT or the specific ERβ agonist DPN for 18 hrs. Uterine weights were higher after E2 or PPT treatment than after DPN or no treatment. ERα mRNA levels decreased significantly in PPT and DPN treated animals as compared to controls. Stromal ERα immunostaining was higher after E2 treatment than in controls. The ERβ mRNA level was lower in the E2 and PPT groups compared with controls. ERβ immunoreactivity was higher in the myometrium after DPN treatment than in controls. The GPER mRNA level was lower in the E2 and DPN groups as compared to the controls, whereas total protein levels did not display any change. The proliferation marker Ki-67 increased after PPT treatment in stroma and myometrium, as compared to controls. Thus, uterine growth and proliferation are predominately regulated via ERα. Also ERβ expression showed regulation via ERα, while GPER expression indicated control via ERβ. This short term treatment did not result in any regulation of the total protein level as determined by Western blot. However, treatment by E2 increased ERα immunostaining in the stroma and DPN augmented ERβ immunostaining in the myometrium. Thus, the estrogen receptors in the rat uterus are differently regulated depending on the ligand and tissue type.

Prostaglandin receptors EP and FP are regulated by estradiol and progesterone in the uterus of ovariectomized rats

BackgroundProstaglandins are important for female reproduction. Prostaglandin-E2 acts via four different receptor subtypes, EP1, EP2, EP3 and EP4 whereas prostaglandin-F2alpha acts through FP. The functions of prostaglandins depend on the expression of their receptors in different uterine cell types. Our aim was to investigate the expression of EPs and FP in rat uterus and to identify the regulation by estradiol, progesterone and estrogen receptor (ER) selective agonists.MethodsWe performed four different rat experiments involving treatments with estradiol, progesterone and ER agonists. Real-time PCR and immunohistochemistry were employed to evaluate receptor expression.ResultsOur results showed that all mRNAs and proteins of EPs and FP are expressed in the rat uterus. The expression pattern and intensity of immunostaining vary between different cell types and treatments. The mRNA expression of all EPs and FP are downregulated by estradiol and the ERalpha specific agonist PPT, whereas the ERbeta specific agonist DPN downregulates only EP2 and EP4. The protein expression however, showed an increase in EP2 and EP3 after estradiol treatment. When treated with estradiol and progesterone in combination, the expressions of EP1 and EP3 are upregulated.ConclusionsRegulation of EPs and FP expression by estradiol appears to be mainly modulated via ERalpha for EP1, EP3 and FP, while EP2 and EP4 also are affected by the ERbeta selective ligand. Our immunohistochemical data shows a cell specific regulation of prostaglandin receptors under the influence of ovarian steroids, where EP2 is estrogen regulated in all uterine tissues examined. EP1 and EP3 are upregulated by the combination of estradiol and progesterone. Thus, our observations indicate that estradiol and progesterone regulate the mRNA and protein expression of EPs and FP in a receptor and tissue specific way.

ChemInform Abstract: Novel Approach to Curatives of Mibyou (Presymptomatic Diseases)

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Structural and histomorphometric evaluations of ferutinin effects on the uterus of ovariectomized rats during osteoporosis treatment

Aims The effects of chronic administration of Ferutinin (phytoestrogen found in the plants of genus Ferula), compared with those elicited by estradiol benzoate, were evaluated, following ovariectomy, on the uterus of ovariectomized rats as regard weight, size, structure and histomorphometry. Main methods The experimental study included 40 female Sprague–Dawley rats, assigned to two different protocols, i.e. preventive and recovering. In the preventive protocol, ferutinin (2 mg/kg/day) was orally administered for 30 days, starting from the day after ovariectomy; in the recovering protocol, ferutinin was administered, at the same dosage, for 30 days starting from the 60th day after ovariectomy, when osteoporosis was clearly established. Its effects were compared with those of estradiol benzoate (1.5 μg per rat twice a week, subcutaneously injected) vs. vehicle-treated ovariectomized controls and vehicle-treated sham-operated controls. Uteri were removed, weighed and analysed under both the structural and histomorphometrical points of view. Key findings Our data show that ferutinin acts, similarly to estradiol benzoate, on the uterus stimulating endometrial and myometrial hypertrophy; this notwithstanding, the phytoestrogen ferutinin, in contrast to estrogen treatment, appears to increase apoptosis in uterine luminal and glandular epithelia. Significance Ferutinin, used in osteoporosis treatment primarily for bone mass recovering, seems in line with an eventual protective function against uterine carcinoma, unlike estrogens so far employed in hormone replacement therapy (HRT).