Uterine Epithelium Research Articles

A gene network of uterine luminal epithelium organizes mouse blastocyst implantation.

PurposeThe receptive endometrium is critical for blastocyst implantation. In mice, after blastocysts enter the uterine cavities on day 4 of pregnancy (day 1 = vaginal plug), blastocyst attachment is completed within 24 h, accompanied by dynamic interactions between the uterine luminal epithelium and the blastocysts. Any failures in this process compromise subsequent pregnancy outcomes. Here, we performed comprehensive analyses of gene expression at the luminal epithelium in the peri‐implantation period.MethodsRNA‐seq combined with laser microdissection (LMD) was used to reveal unique gene expression kinetics in the epithelium.ResultsWe found that the prereceptive epithelium on day 3 specifically expresses cell cycle‐related genes. In addition, days 3 and 4 epithelia express glutathione pathway‐related genes, which are protective against oxidative stresses. In contrast, day 5 epithelium expresses genes involved in glycolysis and the regulation of cell proliferation. The genes highly expressed on days 3 and 4 compared to day 5 are related to progesterone receptor signaling, and the genes highly expressed on day 5 compared to days 3 and 4 are associated with the ones regulated by H3K27me3.ConclusionsThese results suggest that specific gene expression patterns govern uterine functions during early pregnancy, contributing to implantation success.

Epithelial-mesenchymal transition and bi- and multi-nucleated trophoblast cell formation in ovine conceptuses during the peri-implantation period.

Epithelial-mesenchymal transition (EMT), which is common in cancer metastasis, is also observed during developmental processes such as embryo implantation into the maternal endometrium in humans and rodents. However, this process has not been well characterized in the non-invasive type of implantation that occurs in ruminants. To understand whether EMT occurs in ruminant ungulates, ovine conceptuses (embryo plus extraembryonic membranes) from days 15 (P15: pre-attachment), 17 (P17: during attachment), and 21 (P21: post-attachment, day 0 = day of estrus) were evaluated. RNA-seq analysis revealed that the expression of EMT-related transcripts increased on P21. Real-time PCR and western blotting analyses indicated that levels of transcripts and proteins indicative of mesenchyme-related molecules increased on P21, but a minor expression of epithelium-related molecules remained. Immunohistochemical analysis revealed that E-cadherin (CDH1) was localized in the elongated trophectoderm on P15 and P17. On P21, CDH1 was localized to the trophectoderm and on the conceptus cells undergoing differentiation. Vimentin (VIM) was localized in the uterine stroma on P15 and P17, and its expression was observed at the edge of elongating trophoblast on P21. Further, it was found that some bi-nucleated trophoblast cells were present on P17; however, numerous bi- and multi-nucleated trophoblast cells on the uterine epithelium or next to the uterine stroma were found on P21. A minor expression of pregnancy-associated glycoprotein (PAG) transcripts was found on P15 and P17, but a definitive expression of PAGs, transcripts, and proteins was found on P21. Although further investigation is required, these observations indicate that bi-nucleated trophoblast cell formation begins on the day conceptus implantation to the maternal endometrium is initiated, followed by EMT in trophoblast cells. These results suggest that these sequential events are required if pregnancy is to be established in ruminants.

Assessment of 28-day oral exposure to Pueraria candollei var. mirifica (Fabaceae) roots on pituitary-ovarian axis function and selected metabolic parameters in ovary-intact rats

Pueraria candollei var. mirifica (Fabaceae) root (PMR) has recently been developed as a potential selective estrogen receptor modulator (SERM) in menopausal women. Nowadays, many premenopausal women also take dietary PMR supplements, however, the exact biological effects of PMR have not been evaluated. This study included the application of the OECD guideline 407 for the assessment of 28-day oral exposure to PMR on pituitary-ovarian (PO) axis function and metabolic parameters in the premenopausal rat model. Ovary-intact adult rats were orally administrated with 10, 100, 750, 1000, and 1500 mg/kg body weight (BW)/day of PMR powder. The positive estrogenic group was given 2 mg 17β-estradiol (E2)/kg BW/day. Serum levels of reproductive hormones, lipid and thyroid parameters, estrous cycle determination, and histomorphometric and histopathological evaluations of the anterior pituitary, ovary, uterus, vagina, mammary gland, and liver were investigated. PMR displayed neutral effects on uterine, vaginal, and body weights, and circulating E2 and prolactin levels. PMR exerted E2-like effects by i) reducing ovarian and increasing hepatic weights, ii) decreasing serum gonadotropins, iii) lowering serum lipids without altering thyroid parameters, iv) increasing the prevalence of abnormal estrous cycles with prolonged estrus, v) increasing nuclear diameter of anterior pituitary cells, vi) decreasing ovarian size and follicular numbers and increasing follicular degeneration, vii) thickening of uterine myometrium and luminal epithelium, and vaginal epithelium, and viii) induction of mammary alveolar hyperplasia and ductal secretion. Unlike E2, the appearance of very small numbers of focal microvesicular steatosis in hepatocytes demonstrated mild toxicity at high PMR doses. This is the first report that high-dose PMR exerted actions exactly like E2 on gonadotrope-ovarian axis function and histology, lipid, and thyroid parameters without affecting uterine and vaginal growth in ovary-intact rats according to OECD guidelines.

Cyantraniliprole impairs reproductive parameters by inducing oxidative stress in adult female wistar rats

Cyantraniliprole is a synthetic insecticide used to control pests of up to 23 different types of crops. It is able to modulate ryanodine-like calcium channels, which are widely found in the organism of insects and mammals. The objective of this research was to verify the possible reproductive effects of adult female Wistar rats exposure to cyantraniliprole. Animals (67 days old) were exposed to the chemical at doses of 10 or 150 mg/kg/day, orally, for 28 consecutive days (control animals received only the vehicle). Vaginal secretions were collected during the exposure period to assess the regularity of the estrous cycle; the liver, kidneys, pituitary gland, adrenal gland, uterus, and ovaries were collected and weighed; reproductive organs were assessed for histopathological evaluation and for biochemical markers of oxidative stress and progesterone plasma level was measured. Both doses caused negative changes in the morphology and redox system of the uterus and ovaries. Animals exposed to 10 mg/kg also exhibited higher level of plasma progesterone, elevated levels of lipid peroxidation in reproductive organs, increased superoxide dismutase activity in the uterus and glutathione peroxidase activity on the ovary, while the 150 mg/kg group exhibited an increment in estrous cycle length and diminished uterine glandular epithelium. Based on these results, we conclude that cyantraniliprole may have acted as an endocrine disruptor, and its effects are mediated by oxidative stress.

Glycomics reveal that ST6GAL1‐mediated sialylation regulates uterine lumen closure during implantation

ObjectivesImplantation failure is a major cause of prenatal mortality. The uterine lumen closure contributes to embryo adhesion to the uterus, but its underlying mechanisms are largely unknown. Our previous study has reported that endometrial fold extension can lead to uterine lumen closure in pigs. The objective of this study was to reveal molecular mechanisms of the uterine lumen closure by characterizing the molecular basis of the endometrial fold extension during implantation in pigs.Materials and methodsUterine and endometrium tissues during implantation were collected in pigs. MALDI‐TOF MS was used to characterize the N‐glycomic profiles. Histochemistry, siRNA transfection, Western blotting, lectin immumoprecipitation, mass spectrometry and assays of wounding healing and cell aggregation were performed to investigate the molecular basis.ResultsWe observed that uterine luminal epithelium (LE) migrated collectively during endometrial fold extension. For the first time, we identified a large number of N‐glycan compositions from endometrium during implantation using MALDI‐TOF MS. Notably, the α2,6‐linked sialic acid and ST6GAL1 were highly expressed in uterine LE when the endometrial folds extended greatly. Subsequently, the role of ST6GAL1‐mediated 2,6‐sialylation in collective epithelial migration was demonstrated. Finally, we found that ST6GAL1‐mediated α2,6‐sialylation of E‐cadherin may participate in collective migration of uterine LE.ConclusionsThe study reveals a mechanism of uterine lumen closure by identifying that ST6GAL1‐mediated α2,6‐sialylation of cell adhesion molecules contributes to endometrial fold extension through regulating collective migration of uterine LE.

Colposcopic features of cervical oncotropic papilloma-virus infection in patients with various pathology of uterine cervix

In order to estimate the colposcopic manifestations of cervical oncotropic human papilloma-virus (HPV)-infection, a total of 693 patients were examimed. Among them, there were 298 patients with benign tumors pathology, 57 patients with 1-3 Grade cervical dysplasia of mucosa, 50 patients with uterine cervix cancer, 288 healthy women.
 All patients underwent bimanual examination, taking of cervical smears for cytological examination and uterine cervix colposcopy. Diagnosis for HPV16/18 infection was made by the method of polimerase chain reaction.
 А large variety in colposcopic manifestations of HPV-infection was found, namely: areas of atypical vessels, leukoplakia sites,fields of atypical epithelium, iodine-negative sites. It was related to the influence of oncogenic types of HPV infection. In these patients,fields of atypical epithelium, atypical vessels, iodinenegative areas were observed 1.2, 2.5, 10.5 times more frequently, respectively.
 It was found that all varieties of papillomas occurred among patients with pathology, whereas flat condylomas presenting the most difficulties of or diagnosis prevailed in patients with cervical neoplasms and uterine cervix cancer The most pronounced colposcopic evidences of uterine cervix epithelium malignancy were observed in patients with virus-positive uterine cervix cancer.

Increased Systemic Antioxidant Power Ameliorates the Aging-Related Reduction in Oocyte Competence in Mice.

Ovarian aging is associated with elevated oxidative stress and diminished oocyte developmental competence. We aimed to determine the impact of systemic antioxidant treatment in aged mice. Female outbred CF-1 mice were aged for 9 months prior to an 8-week 45 mg Euterpe oleracea (açaí) daily supplement. The açaí treatment induced a threefold increase in serum antioxidant power (FRAP) compared to both young and aged mice (p < 0.0001). Compared to young mice, aged mice had fewer oocytes and reduced blastocyst development (p < 0.0001); açaí did not affect the oocyte numbers, but improved blastocyst formation (p < 0.05). Additionally, açaí alleviated the aging-related decrease in implantation potential (p < 0.01). The aged mice showed evidence of elevated ovarian ER stress (increased whole-ovary PDIA4 expression, granulosa cell and oocyte GRP78 expression, and oocyte PDIA4 protein), reduced oocyte mitochondrial quality (higher PRKN activation and mitochondrial DNA oxidative damage), and dysregulated uterine glandular epithelium. Antioxidant intervention was sufficient to lessen these effects of ovarian aging, likely in part by the upregulation of NRF2. We conclude that açaí treatment is a promising strategy to improve ER and mitochondrial function in the ovaries, thereby ameliorating the decreased oocyte competence that occurs with ovarian aging.

The Immune Barrier of Porcine Uterine Mucosa Differs Dramatically at Proliferative and Secretory Phases and Could Be Positively Modulated by Colonizing Microbiota.

Endometrial immune response is highly associated with the homeostatic balance of the uterus and embryo development; however, the underlying molecular regulatory mechanisms are not fully elucidated. Herein, the porcine endometrium showed significant variation in mucosal immunity in proliferative and secretory phases by single-cell RNA sequencing. The loose arrangement and high motility of the uterine epithelium in the proliferative phase gave opportunities for epithelial cells and dendritic cells to cross talk with colonizing microbial community, guiding lymphocyte migration into the mucosal and glandular epithelium. The migrating lymphocytes were primarily NK and CD8+ T cells, which were robustly modulated by the chemokine signaling. In the secretory phase, the significantly strengthened mechanical mucosal barrier and increased immunoglobulin A alleviated the migration of lymphocytes into the epithelium when the neuro-modulation, mineral uptake, and amino acid metabolism were strongly upregulated. The noticeably increased intraepithelial lymphocytes were positively modulated by the bacteria in the uterine cavity. Our findings illustrated that significant mucosal immunity variation in the endometrium in the proliferative and secretory phases was closely related to intraepithelial lymphocyte migration, which could be modulated by the colonizing bacteria after cross talk with epithelial cells with higher expressions of chemokine.

The role of epithelial progesterone receptor isoforms in embryo implantation

The loss of uterine epithelial progesterone receptor (PGR) is crucial for successful embryo implantation in both humans and mice. The two major isoforms PGRA and PGRB have divergent functions under both physiological and pathological conditions. The present study compares phenotypes and gene signatures of PGRA and PGRB in uterine epithelium using uterine epithelial-specific constitutively expressed PGRA or PGRB mouse models. The cistrome and transcriptome analysis reveals substantial overlap between epithelial PGRA and PGRB, and both disrupt embryo implantation through FOXO1 pathways. Constitutive epithelial PGRA and PGRB expression impairs ESR1 occupancy at the promoter of Lif leading to reduced Lif transcription and further exaggerates SGK1 expression leading to enhanced PI3K-SGK1 activities, and both contribute to the decline of nuclear FOXO1 expression. Our study demonstrates that PGRA and PGRB in the uterine epithelium act on a similar set of target genes and commonly regulate the LIF-SGK1-FOXO1 signaling pathway for embryo implantation.

Regulation of AKT Signaling in Mouse Uterus.

17β-estradiol (E2) treatment of ovariectomized adult mice stimulates the uterine PI3K-AKT signaling pathway and epithelial proliferation through estrogen receptor 1 (ESR1). However, epithelial proliferation occurs independently of E2/ESR1 signaling in neonatal uteri. Similarly, estrogen-independent uterine epithelial proliferation is seen in adulthood in mice lacking Ezh2, critical for histone methylation, and in wild-type (WT) mice treated neonatally with estrogen. The role of AKT in estrogen-independent uterine epithelial proliferation was the focus of this study. Expression of the catalytically active phosphorylated form of AKT (p-AKT) and epithelial proliferation were high in estrogen receptor 1 knockout and WT mice at postnatal day 6, when E2 concentrations were low, indicating that neither ESR1 nor E2 are essential for p-AKT expression and epithelial proliferation in these mice. However, p-AKT levels and proliferation remained estrogen responsive in preweaning WT mice. Expression of p-AKT and proliferation were both high in uterine luminal epithelium of mice estrogenized neonatally and ovariectomized during adulthood. Increased expression of phosphorylated (inactive) EZH2 was also observed. Consistent with this, Ezh2 conditional knockout mice show ovary-independent uterine epithelial proliferation and high epithelial p-AKT. Thus, adult p-AKT expression is constitutive and E2/ESR1 independent in both model systems. Finally, E2-induced p-AKT expression and normal uterine proliferation did not occur in mice lacking membrane (m)ESR1, indicating a key role for membrane ESR1 in AKT activation. These findings emphasize the importance of AKT activation in promoting uterine epithelial proliferation even when that proliferation is not E2/ESR1 dependent and further indicate that p-AKT can be uncoupled from E2/ESR1 signaling in several experimental scenarios.

Amino Acid Transport and Metabolism Regulate Early Embryo Development: Species Differences, Clinical Significance, and Evolutionary Implications.

In this review we discuss the beneficial effects of amino acid transport and metabolism on pre- and peri-implantation embryo development, and we consider how disturbances in these processes lead to undesirable health outcomes in adults. Proline, glutamine, glycine, and methionine transport each foster cleavage-stage development, whereas leucine uptake by blastocysts via transport system B0,+ promotes the development of trophoblast motility and the penetration of the uterine epithelium in mammalian species exhibiting invasive implantation. (Amino acid transport systems and transporters, such as B0,+, are often oddly named. The reader is urged to focus on the transporters’ functions, not their names.) B0,+ also accumulates leucine and other amino acids in oocytes of species with noninvasive implantation, thus helping them to produce proteins to support later development. This difference in the timing of the expression of system B0,+ is termed heterochrony—a process employed in evolution. Disturbances in leucine uptake via system B0,+ in blastocysts appear to alter the subsequent development of embryos, fetuses, and placentae, with undesirable consequences for offspring. These consequences may include greater adiposity, cardiovascular dysfunction, hypertension, neural abnormalities, and altered bone growth in adults. Similarly, alterations in amino acid transport and metabolism in pluripotent cells in the blastocyst inner cell mass likely lead to epigenetic DNA and histone modifications that produce unwanted transgenerational health outcomes. Such outcomes might be avoided if we learn more about the mechanisms of these effects.

Anti-hyperplastic effects of the Dacryodes edulis (Burseraceae) leaves aqueous extract on tamoxifen-induced endometrium hyperplasia on Wistar rat.

Combining tamoxifen, the most common breast cancer hormonal therapy, with natural antitumor substances may prevent its hyperplastic effects on the uterine endometrium. Dacryodes edulis (DE) is traditionally recommended for the treatment of cancerous diseases. To investigate its antiproliferative properties, the present study was designed to assess the ability of the combined administration of tamoxifen with the aqueous extract of DE leaves to inhibit the trophic effect of this hormone therapy on rat uterine endometrium without compromising its non-proliferative effect on breast tissue. Ovariectomized (OVX) female Wistar rats were simultaneously treated with tamoxifen (10mg/kg) intraperitoneally and DE leaves (at doses of 25, 50 and 100mg/kgBW) by gavage. Control groups received either distilled water or tamoxifen alone. Treatments lasted 37days. The 38th day, animals were sacrificed under anesthesia (diazepam: 10mg/kgBW and ketamine: 50mg/kgBW). The relative uterine weight was determined and the histological analysis of the uterus and mammary gland was performed. The oxidative status of the uterus was assessed and the levels of cholesterol and estradiol were evaluated in serum and uterus. Tamoxifen increased uterine weight and induced endometrial hyperplasia. This effect was associated with increased uterine levels of cholesterol (164.22%; p<0.001), estradiol (927.5%; p<0.001) and malondiadehyde (86%; p<0.05), but unchanged antioxidant enzymes activities. The administration of DE leaves unchanged tamoxifen-increased uterine weight but reduced uterine epithelium hypertrophy (56.4%; p<0.01). DE also increased uterine levels of malondiadehyde and antioxidant enzymes. The levels of estradiol and cholesterol in the uterus decreased while no changes were observed in the mammary gland of animals treated with tamoxifen alone or in co-administration with DE. D.edulis has antiproliferative properties and could complement endocrine therapy of estrogen-dependent breast cancer.

Analysis of Healing of Rat Uterine Wall After Full-Thickness Surgical Incision.

We studied the dynamics of morphological changes in the operated segment of the uterine horn of Sprague-Dawley rats during the first 2 weeks of the wound-healing process after a full-thickness surgical incision with regard to the estrous cycle phase. Morphometric parameters of injured uterine right horn were compared with those in the intact left horn of the same animal as a control of changes determined by the hormonal background. It was found that the uterine epithelium in the focus of injury was restored as soon as on day 2 after surgery under the influence of estrous cycle hormones. By day 4, the wound space was completely filled with the endometrial tissue on the side of the uterine lumen and coved by the attached adipose tissue of the mesentery on the side of the abdominal cavity. The thickness of the uterine wall and the uterine lumen differed most strongly between the operated and intact uterine horns during the first 3 days and on day 6 after surgery. The size of the healing area increased during the first three days and reached the peak value by day 3, but then decreased to minimum by day 6.

Expression of retinoic acid signaling pathway in uterus injury induced by procymidone in adolescent mice

To investigate the expression of key genes and proteins of retinoic acid signaling pathway in procymidone-induced uterine injury in adolescent mice, and analyze the relationship between the signaling pathway and female reproductive damage. The 3-week age ICR mice were randomly divided into low, medium, and high-dose groups and one control group with 8 mice in each group by weight. The low, medium and high dose groups were respectively given 50, 100 and 200 mg/(kg·d) procymidone orally for 21 days continuously, while the control group was given equal volume of soybean oil. After the mice were sacrificed, the uterus was taken from both sides for observing the histological changes in the cross-sectional slices of the uterus, the detection of the expression abundance of genes which related to the retinoic acid signaling pathway by the real-time fluorescent quantitative PCR, and the measurement of ALDH2 and CYP26 a1 proteins expression by Western blot. The body weight of mice in low-dose, medium-dose and high-dose groups were(27.50±1.49) g, (27.72±1.40) g and(26.89±1.19) g, respectively, which were lower than those in control group(31.48±1.14) g(P&lt;0.05). The density of uterine lining monolayer columnar epithelium and lamina propria tubular uterine glands gradually decreases, at the same time the uterine folds become less with the dose of procymidone increases. adh1, ad/2, aldh1a1 in each experimental group were higher than those in the control group(P&lt;0.05); the expression levels of aldh1a2 and aldh1a3 genes in the middle and high dose groups were higher than those in the control group(P&lt;0.05); the expression levels of retinoic acid nuclear receptor rarα, rarγ, rxrα and rxrβ genes in the high-dose group were higher than those in the control(P&lt;0.05); yet the expression levels of cyp26a2 and cyp26a3 in the high-dose group were lower than those in the control group(P&lt;0.05); the jnk family in medium and high dose groups were higher than the control(P&lt;0.05). The expression of ALDH2 in each experimental group was higher than that in the control group, and increased with the increase of the dose(P&lt;0.05); the expression of CYP26 a1 in each experimental group was not significantly different from that of the control group. The retinoic acid signal pathway is activated in procymidone-induced uterine injury in mice, then regulates the increase of the expression of jnk family, leading to the damage.

RETROSPECTIVE ANALYSIS OF CERVICAL CYTOPATHOLOGICAL EXAMS PERFORMEDAT AT THE LABORATORY OF PATHOLOGICAL ANATOMY AND CYTOPATHOLOGY OF THE HOSPITAL ESCOLA ÁLVARO ALVIM

Each year about 272,610 new cases of cancer are diagnosed in Brazil, being cervical cancer the third most incident among women. Our country is among those that have made the most progress in consolidating the integrated cancer tracking and surveillance system. This article aims to collect sociodemographic and clinicopathological data from patients who underwent cervical cytopathological examinations at the Laboratory of Pathological Anatomy and Cytopathology at the Hospital Escola Álvaro Alvim (HEAA) from 2014 to 2018, considering a retrospective and longitudinal observation of the data. Sociodemographic and clinicopathological data were collected from 121,044 patients, and it was observed that women from Campos dos Goytacazes (84.7%) over 40 years old (56.8%) were the most prevalent at the service. The following cytological characteristics that predominated in these patients were: absence of atrophy (83.6%) or metaplasia (92.6%) of the uterine epithelium, presence of microorganisms (96.4%) and inflammation (97.2%). The presence of cell atypia (6.5%), squamous intraepithelial lesion (2%) and malignant neoplasm (0.1%) was also observed. Therefore, it becomes possible to highlight the importance of cytological examination in the process of diagnosis of malignant neoplasms of the uterine cervix, being essential for a better control and adequate screening, implementing an effective early diagnosis. It also demonstrates the profile of the patients examined at the Pathological Anatomy and Cytopathology Laboratory of HEAA, as well as the scope of this service for early diagnosis of cervical cancer in the North and Northwest Fluminense.

Ral GEF with the PH Domain and SH3 Binding Motif 1 Regulated by Splicing Factor Junction Plakoglobin and Pyrimidine Metabolism Are Prognostic in Uterine Carcinosarcoma.

Uterine carcinosarcoma (UCS) is a highly invasive malignant tumor that originated from the uterine epithelium. Many studies suggested that the abnormal changes of alternative splicing (AS) of pre-mRNA are related to the occurrence and metastasis of the tumor. This study investigates the mechanism of alternative splicing events (ASEs) in the tumorigenesis and metastasis of UCS. RNA-seq of UCS samples and alternative splicing event (ASE) data of UCS samples were downloaded from The Cancer Genome Atlas (TCGA) and TCGASpliceSeq databases, several times. Firstly, we performed the Cox regression analysis to identify the overall survival-related alternative splicing events (OSRASEs). Secondly, a multivariate model was applied to approach the prognostic values of the risk score. Afterwards, a coexpressed network between splicing factors (SFs) and OSRASEs was constructed. In order to explore the relationship between the potential prognostic signaling pathways and OSRASEs, we fabricated a network between these pathways and OSRASEs. Finally, validations from multidimension platforms were used to explain the results unambiguously. 1,040 OSRASEs were identified by Cox regression. Then, 6 OSRASEs were incorporated in a multivariable model by Lasso regression. The area under the curve (AUC) of the receiver operator characteristic (ROC) curve was 0.957. The risk score rendered from the multivariate model was corroborated to be an independent prognostic factor (P < 0.001). In the network of SFs and ASEs, junction plakoglobin (JUP) noteworthily regulated RALGPS1-87608-AT (P < 0.001, R = 0.455). Additionally, RALGPS1-87608-AT (P = 0.006) showed a prominent relationship with distant metastasis. KEGG pathways related to prognosis of UCS were selected by gene set variation analysis (GSVA). The pyrimidine metabolism (P < 0.001, R = −0.470) was the key pathway coexpressed with RALGPS1. We considered that aberrant JUP significantly regulated RALGPS1-87608-AT and the pyrimidine metabolism pathway might play a significant part in the metastasis and prognosis of UCS.

Cyanidin-3-O-glucoside ameliorates cadmium induced uterine epithelium proliferation in mice

Cadmium (Cd) is an environmental pollutant and endocrine disrupter, abundantly present in water, food, and soil. Accumulation of Cd in the body can negatively affect female reproduction; especially the uterus is exceptionally sensitive to the toxic actions of Cd. The anthocyanin cyanidin-3-O-glucoside (C3G) is a naturally occurring phenolic compound in fruits and plants that can antagonize the toxic effects of Cd. This capacity makes C3G a possible candidate to prevent Cd-induced female infertility. The present study aimed to investigate: 1) whether C3G intake could prevent Cd-induced female reproductive toxicity, and 2) the underlying mechanisms responsible for this protective effect. The results of our study indicated that Cd exposure did not affect ovarian function, but induced hypertrophy of the uterine endometrium. Oral intake of C3G markedly reduced the effects of Cd exposure on the thickness of the uterine epithelium cells. Transcriptomic analysis of the endometrium revealed that C3G intake had anti-estrogenic effects, attenuating Cd-induced endometrial epithelial cell proliferation by inhibiting estrogen-responsive genes, enhancing epithelial progesterone receptor expression, and regulating Klf4 expression. The current findings implicate that C3G has the potential to be used as a dietary supplement based on its capacity to intervene in Cd-induced female reproductive toxicity.

Transcriptomic Analysis of STAT1/3 in the Goat Endometrium During Embryo Implantation.

Interferon tau (IFNT), a pregnancy recognition signal in ruminants, promotes the establishment of embryo implantation by inducing the expression of interferon-stimulated genes (ISGs) via the Janus kinase/signal transducer and activator of transcription (JAK/STAT) signaling pathway. However, the precise regulatory mechanism of IFNT in goat embryo implantation remains largely unknown. In this study, we performed RNA sequencing of goat endometrial epithelial cells (gEECs) with or without 20 ng/mL IFNT treatment. Differential comparison showed that there were 442 upregulated differentially expressed genes (DEGs) and 510 downregulated DEGs. Bioinformatic analyses revealed that DEGs were significantly enriched in immune-related functions or pathways. The qRT-PCR validation results showed that the expression levels of STAT family members (STAT1, STAT2, and STAT3) were significantly upregulated in gEECs after IFNT treatment, which is in agreement with the RNA-seq data. Meanwhile, the protein levels of p-STAT1 and p-STAT3 increased significantly in gEECs after 6 and 24 h of IFNT treatment, respectively. Further in vivo experiments also confirmed that both mRNA and protein phosphorylation levels of STAT1 and STAT3 in the uterus on day 18 of pregnancy (P18) were significantly increased compared to those on day 5 (P5) and day 15 of pregnancy (P15). On P5, STAT1 and STAT3 proteins were primarily located in the uterine luminal epithelium (LE) and glandular epithelium (GE), and were also detected in the stromal cells. The intense immunostaining of STAT1 and STAT3 proteins were decreased on P15 and then increased on P18, especially in the superficial GE and subepithelial stromal cells. Moreover, p-STAT1 and p-STAT3 were highly expressed in the deep GE on P18. Collectively, these results highlight the role of IFNT in regulating endometrial receptivity in gEECs and uncover the temporal and spatial changes in the expression of STAT1/3 during embryo implantation in the goat endometrium.

Sperm interaction with the uterine innate immune system: toll-like receptor 2 (TLR2) is a main sensor in cattle.

During the passage through the female reproductive tract, sperm interact with various compartments and their immune systems. The immune system that protects the female against pathogens also could destroy sperm or prevent them from reaching the site of fertilisation. In particular, the uterine innate immune response is crucial from the perspectives of both the sperm and the uterus. Following insemination, sperm immediately start to trigger inflammation in the uterus by entering uterine glands and activating an innate immune response. In cattle, the activation occurs mainly via TLR2 signalling, if not the only one, between sperm and the uterine epithelium lining the glands. This acute immune response is manifested as the upregulation of mRNA expression of IL8, TNFA, IL1B , and PGES . As a consequence, many sperm are trapped by polymorphonuclear neutrophils, the first and major component of innate immunity. The sperm-induced uterine innate immune responses apparently serve to clear the uterus of excess sperm and, importantly, prepare the endometrium for implantation. Pathophysiological conditions in the uterus seriously disrupt this phenomenon, and thus could directly decrease fertility.

Uterine cellular changes during mammalian pregnancy and the evolution of placentation†.

There are many different forms of nutrient provision in viviparous (live-bearing) species. The formation of a placenta is one method where the placenta functions to transfer nutrients from mother to fetus (placentotrophy), to transfer waste from the fetus to the mother, and to perform respiratory gas exchange. Despite having the same overarching function, there are different types of placentation within placentotrophic vertebrates, and many morphological changes occur in the uterus during pregnancy to facilitate formation of the placenta. These changes are regulated in complex ways but are controlled by similar hormonal mechanisms across species. This review describes current knowledge of the morphological and molecular changes to the uterine epithelium preceding implantation among mammals. Our aim is to identify the commonalities and constraints of these cellular changes to understand the evolution of placentation in mammals and to propose directions for future research. We compare and discuss the complex modifications to the ultrastructure of uterine epithelial cells (UEC) and show that there are similarities in the changes to the cytoskeleton and gross morphology of the UEC, especially of the apical and lateral plasma membrane of the cells during the formation of a placenta in all eutherians and marsupials studied to date. We conclude that further research is needed to understand the evolution of placentation among viviparous mammals, particularly concerning the level of placental invasiveness, hormonal control, and genetic underpinnings of pregnancy in marsupial taxa.