Endometrial Layer Research Articles

Single- versus double-layer closure of the caesarean (uterine) scar in the prevention of gynaecological symptoms in relation to niche development \u2013 the 2Close study: a multicentre randomised controlled trial

BackgroundDouble-layer compared to single-layer closure of the uterus after a caesarean section (CS) leads to a thicker myometrial layer at the site of the CS scar, also called residual myometrium thickness (RMT). It possibly decreases the development of a niche, which is an interruption of the myometrium at the site of the uterine scar. Thin RMT and a niche are associated with gynaecological symptoms, obstetric complications in a subsequent pregnancy and delivery and possibly with subfertility.MethodsWomen undergoing a first CS regardless of the gestational age will be asked to participate in this multicentre, double blinded randomised controlled trial (RCT). They will be randomised to single-layer closure or double-layer closure of the uterine incision. Single-layer closure (control group) is performed with a continuous running, unlocked suture, with or without endometrial saving technique. Double-layer closure (intervention group) is performed with the first layer in a continuous unlocked suture including the endometrial layer and the second layer is also continuous unlocked and imbricates the first. The primary outcome is the reported number of days with postmenstrual spotting during one menstrual cycle nine months after CS. Secondary outcomes include surgical data, ultrasound evaluation at three months, menstrual pattern, dysmenorrhea, quality of life, and sexual function at nine months. Structured transvaginal ultrasound (TVUS) evaluation is performed to assess the uterine scar and if necessary saline infusion sonohysterography (SIS) or gel instillation sonohysterography (GIS) will be added to the examination. Women and ultrasound examiners will be blinded for allocation. Reproductive outcomes at three years follow-up including fertility, mode of delivery and complications in subsequent deliveries will be studied as well. Analyses will be performed by intention to treat. 2290 women have to be randomised to show a reduction of 15% in the mean number of spotting days. Additionally, a cost-effectiveness analysis will be performed from a societal perspective.DiscussionThis RCT will provide insight in the outcomes of single- compared to double-layer closure technique after CS, including postmenstrual spotting and subfertility in relation to niche development measured by ultrasound.Trial registrationDutch Trial Register (NTR5480). Registered 29 October 2015.

The efficacy of Ankaferd Blood Stopper® in an experimental Asherman syndrome model created in rats.

Objective:Asherman syndrome (AS) is a progressive disease involving menstrual disorders, recurrent pregnancy losses, and infertility developing as a result of partial or full blockade of the uterine cavity with adhesions. AS generally develops after trauma to the basal layer of the endometrium. In spite of a variety of methods such as adhesiolysis, inserting intrauterine devices, and administering high doses of estrogen, treatments remain insufficient. This study aimed to assess the effects of local intrauterine Ankaferd Blood Stopper (ABS) administration in inducing endometrial proliferation and building a normal endometrial layer in a rat model.Materials and Methods:AS was induced in 30 female Wistar albino rats. The rats were randomized into three groups:Group 1: AS groupGroup 2: AS + serum physiologic (SP) groupGroup 3: AS + ABS groupAS model was induced in all animals. The uterine horns were harvested after 15 days of therapy and investigated for inflammation, fibrosis, and immunohistochemical (IHC) markers.Results:Compared with the other groups, fibrosis, and inflammation were significantly reduced in group 3 (chi-square, p=19.000, 0.001 and 26.365, <0.001, respectively). The IHC assessment showed that the tumor necrosis factor-α receptor levels were not different (Kruskal-Wallis H=0.091, p=0.995), but the interleukin (IL)-1β and IL-6 expression was reduced significantly in group 3 (H, p=18.706, <0.001, and 22.114, <0.001, respectively).Conclusion:The therapeutic effects of local administration of ABS in rats with AS model were demonstrated histopathologically and immunohistochemically. Based on these results, ABS administration in addition to the current treatments for AS may increase the treatment success and reduce the need for advanced treatment.

Morphological changes in the genitals of cows with uterine subinvolution

&nbsp; The experiments were carried out in the farms of the Volgograd and Saratov regions. With uterus subinvolution, hypersensitivity of the skin of the back, croup, anogenital zone, increased excitability of the nasal cavity, probing gait, and lordous body setting were established. An increase and compaction of the patellar and superficial inguinal lymph nodes were marked, the pre-blade and submandibular lymph nodes were unchanged. Tachycardia is set. On the 7th day after calving, cows with uterus subinvolution had puffiness and diffuse cellular infiltration of a compact endometrial layer, puffiness of muscle fibers and necrobiotic processes in the epithelium of the uterine glands. On the 14th day, dystrophy and desquamation of the integumentary epithelium was clearly noted. On the 28th day, the uterine mucosa was characterized by the absence of the epithelial lining, diffuse cellular infiltration of the

Porous scaffolds from droplet microfluidics for prevention of intrauterine adhesion

Severe intrauterine adhesions (IUAs) have a great negative impact on women's psychological and reproductive health. It remains a significant challenge to prevent postoperative IUAs because of the complications of various clinical preventive measures and incompatibility of uterine cavity morphology. Herein, we present a new drug-loadedporous scaffold based on a microfluidic droplet template, which combines the characteristics of the artificial biocompatible material GelMA and the natural polysaccharide material Na-alginate. By changing the containers that collect the microfluidic droplets, the porous scaffold conforming to the shape of the uterine cavity could be obtained. The porous structure, mechanical property, and flexibility impart the scaffold with compressibility and send it to the uterus through the vagina. In addition, the external–internal connected open structures could load and control the release of drugs to repair the damaged region continuously in vivo. To verify the antiadhesion and repair of drug-loaded porous scaffolds, we tested the system in the rat model of IUAs, and it was demonstrated that the system had the ability to improve neovascularization, cellularize the damaged tissue, and repair the endometrium. These features provide the drug-loaded porous scaffolds with new options for the improvement of postoperative IUAs. Statement of SignificanceIntrauterine adhesions are caused by various causes of damage to the endometrial basal layer, thus leading to part or entire adhesions in the cervical or uterine cavity. Clinically, various preventive measures reach the barrier effect through the physical barrier, which are difficult to further promote the repair of the damaged endometrium, and most of them have apparent side effects. This study aims to prepare compressible and biodegradable three-dimensional porous drug-loading biological scaffolds. GelMA and Na-alginate have desirable biocompatibility. The interconnect porous scaffolds, which were prepared through the combination of biomaterials and single emulsion microfluidics, not only have compressibility but also provide space for drug delivery and release. This system can further promote the repair of the endometrium while preventing adhesion.

THE STUDY OF IMMUNOHISTOCHEMICAL EXPRESSION OF CERTAIN PRO- AND ANTIAPOPTOTHIC FACTORS IN ENDOMETRY OF PATIENTS WITH ADENOMIOSIS

Objective: to study the immunohistochemical expression of proand anti-apoptotic factors — FasL(CD95), TNF-a, p65 NFkB, and granzyme B in the endometrium of patients with adenomyosis. Material and Methods. The endometrial samples, taken during the proliferative phase of the cycle, while carrying out paypel biopsy and hysteroscopy in 41 women aged 37 to 48 years with adenomyosis. The comparison group consisted of 25 women with infertility. The study of TNF-a, Granzym B, NFkB immunohistochemical expression in the development and progression of adenomyosis was performed using monoclonal antibodies. The results of reaction were evaluated by semiquantitative method. Statistical analysis was performed using the software package Biostat Apps MicrosoftR Excel full-featured office Microsoft Office 2010 package. Results. In the comparison group, the expression of TNF-a and NFkB in endometrium was not evident. In the group of patients with adenomyosis, a marked expression of these markers in epithelial and stromal cells was observed. Granzym B expression was detected in the cytoplasm of leucocytes of the stroma of the endometrial functional layer with no statistically significant differences between the groups. Conclusion. Presumably, given the expression peaks of both TNF-a, p65 NFkB, the observed in adenomyosis increase (compared to normal) in expression of these molecules does not mean readiness of epithelial cells of the endometrial functional layer to apoptosis, as is the norm, upon the occurrence of menstruation, but it means readiness of these cells to proliferate. The absence of statistically significant differences in the number of CD56-positive endometrial stromal granulocytes and endometrial NK-cells, determined by Granzym B expression in these cells, is also an indirect evidence of a low level of readiness to apoptosis. And statistically significantly less expression of FasL(CD95) in women with adenomyosis. That is, TNF-a and NFkB at adenomyosis, probably, play the role of cell survival factors.

Menstrual cycle in four New World primates: Poeppig's woolly monkey (Lagothrix poeppigii), red uakari (Cacajao calvus), large-headed capuchin (Sapajus macrocephalus) and nocturnal monkey (Aotus nancymaae)

Genital organs from 33 nocturnal monkeys Aotus namcymaae, 29 Poeppig's woolly monkeys (Lagothrix poeppigii), 21 red uakaris (Cacajao calvus) and 11 large-headed capuchins (Sapajus macrocephalus) were histologically analyzed in order to describe the endometrial changes related to the ovarian cycle. A. nancymaae and S. macrocephalus showed histological evidence of menstrual cycle with the detachment of the most superficial endometrium and the subepithelial reabsorption of the endometrial functional layer, explaining the extensive presence of both hemosiderin and fibrin clusters in the early follicular stages. In L. poeppigii, despite the presence of fibrin clusters promoting the remodeling of the endometrium, we did not observe the detachment of the functional layer of the endometrium, suggesting that this species presents a non-menstruating cycle. Finally, C. calvus showed no histological sign of menstrual phase. This reproductive information is useful to improve assisted reproductive techniques in non-human primates, and give us opportunity for comparative studies on the evolution of animal reproductive biology, including humans.

INTERCELLULAR INTERACTIONS IN THE ENDOMETRIAL HYPERPLASIA-RELATED INFLAMMATION DEVELOPMENT

Proliferation and apoptosis play an important role in cyclic changes in the healthy canine endometrium. Proteins of the Bcl-2-family are known to be involved in the regulation of apoptosis. However, only few reports mention their expression patterns during cystic endometrial hyperplasia (CEH). In order to correlate proliferative and apoptotic processes, expression of the apoptosis-regulatory proteins Bcl-2 (anti-apoptotic) and Bax (pro-apoptotic) in healthy and cystic hyperplastic endometrial tissue as well as in pyometra was investigated. Uteri from 33 bitches were assigned to three groups: group 1 - healthy endometrium (n = 12), group 2 – CEH (n = 17) and group 3 - pyometra (n = 4). Markers for proliferation (Ki-67) and apoptosis (activated caspase-3 and TUNEL-method) as well as expression of Bcl-2 and Bax were determined in all endometrial layers. For groups 1 and 2 this was done during endometrial gland secretion in mid and late luteal phase (mLP, lLP), endometrial reparation in early anestrus (eAE) and in the regenerated endometrium in late anestrus (lAE). For group 3 only the late luteal phase was investigated.In group 1, cyclic proliferation patterns were found predominantly in superficial glands (SG) and stroma, whereas progesterone-mediated low expression levels coincided with high apoptosis rates in the basal glands (BG). In eAE, higher apoptotic activity was detected compared to lLP and lAE. Bcl-2 and Bax expression levels showed an inverse cyclic relationship in all tissue layers. In the stroma, in eAE, a rise in proliferative activity and concomitant increase in anti-apoptotic Bcl-2 expression levels was found, indicating that this layer serves as a source for endometrial regeneration.In CEH, no or limited cyclic patterns of proliferation, apoptosis, Bcl-2 and Bax were found. Increased proliferation rates coincided with deregulated apoptosis. Besides the glandular compartments, the stroma played an important role in the pathogenesis of canine CEH. In case of pyometra, both proliferation and apoptosis increased, indicating irreversible damage of the inflamed canine endometrium.In conclusion Bcl-2 and Bax play a role both in the physiological regenerative processes of the cyclic canine endometrium and in deregulating proliferation and apoptosis in CEH and pyometra.

Proliferative and apoptotic changes in the healthy canine endometrium and in cystic endometrial hyperplasia

Proliferation and apoptosis play an important role in cyclic changes in the healthy canine endometrium. Proteins of the Bcl-2-family are known to be involved in the regulation of apoptosis. However, only few reports mention their expression patterns during cystic endometrial hyperplasia (CEH). In order to correlate proliferative and apoptotic processes, expression of the apoptosis-regulatory proteins Bcl-2 (anti-apoptotic) and Bax (pro-apoptotic) in healthy and cystic hyperplastic endometrial tissue as well as in pyometra was investigated. Uteri from 33 bitches were assigned to three groups: group 1 - healthy endometrium (n = 12), group 2 – CEH (n = 17) and group 3 - pyometra (n = 4). Markers for proliferation (Ki-67) and apoptosis (activated caspase-3 and TUNEL-method) as well as expression of Bcl-2 and Bax were determined in all endometrial layers. For groups 1 and 2 this was done during endometrial gland secretion in mid and late luteal phase (mLP, lLP), endometrial reparation in early anestrus (eAE) and in the regenerated endometrium in late anestrus (lAE). For group 3 only the late luteal phase was investigated.In group 1, cyclic proliferation patterns were found predominantly in superficial glands (SG) and stroma, whereas progesterone-mediated low expression levels coincided with high apoptosis rates in the basal glands (BG). In eAE, higher apoptotic activity was detected compared to lLP and lAE. Bcl-2 and Bax expression levels showed an inverse cyclic relationship in all tissue layers. In the stroma, in eAE, a rise in proliferative activity and concomitant increase in anti-apoptotic Bcl-2 expression levels was found, indicating that this layer serves as a source for endometrial regeneration.In CEH, no or limited cyclic patterns of proliferation, apoptosis, Bcl-2 and Bax were found. Increased proliferation rates coincided with deregulated apoptosis. Besides the glandular compartments, the stroma played an important role in the pathogenesis of canine CEH. In case of pyometra, both proliferation and apoptosis increased, indicating irreversible damage of the inflamed canine endometrium.In conclusion Bcl-2 and Bax play a role both in the physiological regenerative processes of the cyclic canine endometrium and in deregulating proliferation and apoptosis in CEH and pyometra.

MRI Imaging of Focal Adenomyosis and Adenomyotic Cyst: Case Report

Adenomyosis is defined by the presence of ectopic endometrial glands and stroma within the myometrium. This happens when the normal boundary between the endometrial basal layer and the myometrium is disrupted. It proposed that it may be due to uterine trauma, pregnancy, postpartum endometritis, or caesarean delivery. Adenomyosis has been noted to occur in about 30% of the general female population and the reported prevalence of adenomyosis in hysterectomy specimens varies from 5% to 70%. We report a case of a 42 year old female, nulligravida, with a medical history of complete spontaneous miscarriage five years ago; with uncontrolled bleeding which it need to be treated with cervical cerclage. Actually she has a menstrual menometrorrhagia and dysmenorrhea treated with oral contraceptive pills but it did not stop. Transvaginal sonography showed a globular uterine enlargement with one leiomyoma and uterine wall thickening. Vascular malformation or adenomyosis were suspected. A MRI was performed which it showed findings in respect with adenomyosis.

S-equol Exerts Estradiol-Like Anorectic Action with Minimal Stimulation of Estrogen Receptor-α in Ovariectomized Rats.

Chronic estrogen replacement in ovariectomized rats attenuates food intake and enhances c-Fos expression in the suprachiasmatic nucleus (SCN), specifically during the light phase. S-equol, a metabolite of daidzein, has a strong affinity for estrogen receptor (ER)-β and exerts estrogenic activity. The purpose of the present study was to elucidate whether S-equol exerts an estrogen-like anorectic effect by modifying the regulation of the circadian feeding rhythm in ovariectomized rats. Ovariectomized female Wistar rats were divided into an estradiol (E2)-replaced group and cholesterol (vehicle; Veh)-treated group. These animals were fed either a standard diet or an S-equol-containing diet for 13 days. Then, the brain, uterus, and pituitary gland were collected along with blood samples. In the rats fed the standard diet, E2 replacement attenuated food intake (P < 0.001) and enhanced c-Fos expression in the SCN (P < 0.01) during the light phase. Dietary S-equol supplementation reduced food intake (P < 0.01) and increased c-Fos expression in the SCN (P < 0.01) in the Veh-treated rats but not in the E2-replaced rats during the light phase. Dietary S-equol did not alter ER-α expression in the medial preoptic area or the arcuate nucleus, nor did dietary S-equol affect pituitary gland weight or endometrial epithelial layer thickness. By contrast, E2 replacement not only markedly decreased ER-α expression in these brain areas (P < 0.001) but also increased both the pituitary gland weight (P < 0.001) and the endometrial epithelial layer thickness (P < 0.001). Thus, dietary S-equol acts as an anorectic by modifying the diurnal feeding pattern in a manner similar to E2 in ovariectomized rats; however, the mechanism of action is not likely to be mediated by ER-α. The data suggest a possibility that dietary S-equol could be an alternative to hormone replacement therapy for the prevention of hyperphagia and obesity with a lower risk of adverse effects induced by ER-α stimulation.

THE EFFECTIVENESS OF THE COMBINATIONS OF CALCITRIOL AND ETHYNIL ETHYL ESTRADIOL TO DECREASE OSTEOPOROSIS AND ENDOMETRIAL CANCER RISKS IN OVARIECTOMIZED RATS

The objective of this research was to study the effectiveness of calcitriol and ethynil ethyl estradiol combinations to decrease osteoporosis and endometrial cancer risks in ovariectomized Wistar rats. Twenty five 8-week old female Wistar rats were randomly divided into five groups (normal controlled rats/NK, ovariectomized rats/OVK, ovariectomized rats + calcitriol supplementation/OVD, ovariectomized rats + ethynil ethyl estradiol supplementation/OVE, and ovariectomized rats + calcitriol + ethynil ethyl estradiol supplementation/OVDE). At the end of the study, all rats were weighed and euthanized with 10% ketamine and 2% xylazine. Uterus and left femur were taken and fixed in 10% formaldehyde solution for histopathological examination using hematoxylin and eosin stain. Uterus was weighed before the fixation. The results showed that the percentage of uterus weight in OVK was significantly decreased compared to NK. Meanwhile, the percentage of uterus weight in OVDE was significantly increased compared to OVK. Histopathological features of the uterus in OVK were atrophy, reduction of myometrial and endometrial layers thickness, and formation of cuboidal epithelium in the endometrial lumen. However, the thickness of myometrial and endometrial layers in OVDE were increased, and its endometrial lumen was lined with metaplastic and hyperplastic squamous cell. Histopathological features of distal femur epiphysis in OVK ras showed fewer trabecular spiculums and more adipocyte in the bone marrow compared to NK. However, OVDE had more trabecular bone spiculum and less adipocyte in the bone marrow compared to OVK. In conclusion, the combination of calcitriol and ethynil ethyl estradiol supplementation could reduce osteoporosis, but increased the endometrial cancer risk in ovariectomized Wistar rats.

Reconstructing Lineage Hierarchies of Mouse Uterus Epithelial Development Using Single-Cell Analysis.

SummaryThe endometrial layer comprises luminal and glandular epithelia that both develop from the same simple layer of fetal uterine epithelium. Mechanisms of uterine epithelial progenitor self-renewal and differentiation are unclear. This study aims to systematically analyze the molecular and cellular mechanisms of uterine epithelial development by single-cell analysis. An integrated set of single-cell transcriptomic data of uterine epithelial progenitors and their differentiated progenies is provided. Additionally the unique molecular signatures of these cells, characterized by sequential upregulation of specific epigenetic and metabolic activities, and activation of unique signaling pathways and transcription factors, were also investigated. Finally a unique subpopulation of early progenitor, as well as differentiated luminal and glandular lineages, were identified. A complex cellular hierarchy of uterine epithelial development was thus delineated. Our study therefore systematically decoded molecular markers and a cellular program of uterine epithelial development that sheds light on uterine developmental biology.

Caprine Endometrial Mesenchymal Stromal Stem Cell: Multilineage Potential, Characterization, and Growth Kinetics in Breeding and Anestrous Stages.

The endometrial layer of the uterus contains a population of cells with similar characteristics of mesenchymal stem cells (MSCs). In the present study, caprine endometrial mesenchymal stromal stem cells (En-MSCs) characters and differentiation potential to chondrogenic, osteogenic, and adipogenic cell lines as well as their growth kinetics in breeding and anestrous stages were evaluated. En-MSCs were enzymatically isolated from endometrial layer of the uterus of adult goats and were cultured and subcultured until passage 4. The growth kinetics and population doubling time (PDT) of caprine En-MSCs in breeding and anestrous stages were determined. En-MSCs in passage 4 were used for the karyotyping and differentiation into chondrocytes, osteocytes, and adipocytes. The PDT in anestrus phase was 40.6 h and in cyclic goats was 53 h. En-MSCs were fibroblast-like in all passages. The number of chromosomes was normal (2n = 60) with no chromosomal instability. Chondrogenic, osteogenic, and adipogenic differentiation of En-MSCs was confirmed by staining with Alcian blue, Alizarin red, and Oil Red O, respectively. Caprine En-MSCs demonstrated to be an alternative source of MSCs for cell therapy purposes in regenerative medicine.

Cellular Localization and Regulation of Expression of the PLET1 Gene in Porcine Placenta.

The placenta expressed transcript 1 (PLET1) gene, which is expressed in placentas of pigs and mice, has been found to have a potential role in trophoblast cell fate decision in mice. Results of this study showed that the porcine PLET1 mRNA and protein were expressed exclusively in trophoblast cells on Days 15, 26, 50, and 95 of gestation (gestation length in the pig is 114 days), indicating that the PLET1 could be a useful marker for porcine trophoblast cells. Additionally, PLET1 protein was found to be redistributed from cytoplasm to the apical side of trophoblast cells as gestation progresses, which suggests a role of PLET1 in the establishment of a stable trophoblast and endometrial epithelial layers. In addition, two transcripts that differ in the 3′ UTR length but encode identical protein were identified to be generated by the alternative cleavage and polyadenylation (APA), and the expression of PLET1-L transcript was significantly upregulated in porcine placentas as gestation progresses. Furthermore, we demonstrated the interaction between the miR-365-3p and PLET1 gene using luciferase assay system. Our findings imply an important role of PLET1 in the placental development in pigs.

Monosodium glutamate depresses the function of female reproductive system in rat by promoting oxidative stress induced changes in the structure of uterus

The aim of the present study was to examine the effects of MSG on the function of the uterus. We have observed significant degenerative changes in the endometrial and myometrial layers of the uterus in MSG exposed rats in a dose dependent manner compared to wall structure of the uterus of control rats. To elucidate the causes of MSG induced necrosis of the uterine wall structure, the activities of the cellular oxidative stress indices in MSG exposed uterus have been studied. We have found significant decrease in the activities of SOD, CAT, GR. and GPx, and significant increase in the activity of GST in MSG exposed uterine tissue homogenate. Besides, the level of MDA in MSG exposed uterine tissue homogenate has been increased significantly. The results suggest that the degeneration of MSG induced uterine tissue might be due to enhanced oxidative stress and increased lipid peroxidation in uterine tissue cells. In conclusion, MSG depresses the function of female reproductive system in rats probably by promoting oxidative stress induced changes in the wall structure of uterus.

Xenograft of Mus musculus ovary in the uterus of Rattus norvegicus after induction of pseudopregnancy

Xenograft of gonads such as ovarian tissue can preserve fertility in patients at risk of infertility after radiotherapy or chemotherapy and also is valuable in preserving fertility in mammalian species. The purpose of this investigation was to preserve mouse (Mus musculus) ovarian tissue after xenografting in uterine lumen of rat (Rattus norvegicus) immunoprivileged by pseudopregnancy. Ten adult female Balb/c mice and seven female and four male Sprague-Dawley rats were enrolled. Seven mice were selected for transplantation, and three mice were euthanized and their ovaries were removed as controls. Female Sprague-Dawley rats in proestrous stage were mated with vasectomized male rats to induce pseudopregnancy 7 days after mating. Both ovaries of mice in diestrous stage were simultaneously and gently transferred into the uterine lumen of pseudopregnant rat. Fourteen days after xenotransplantation, the ovaries were removed and were histologically evaluated. Fourteen days after xenotransplantation, four out of seven transplanted mice ovaries were not rejected in rat uterine cavities. From 14 ovaries, eight ovaries could survive in the uterine lumen and were attached to the endometrial layer of rat uterus. Six ovaries lacked active large follicles and corpora lutea but no evidence of tissue necrosis was noted. Two ovaries showed evidence of inactive corpora lutea, secondary follicles. Also, primordial follicles were detectable in these two ovaries. Capillaries filled with blood cells in these ovaries denoted to the signs of angiogenesis. Therefore, survival of the xenotransplanted ovaries of mice in the rat uterine cavity denoted to the possibility of xenograft of gonads such as ovarian tissue in uterine lumen to preserve fertility in patients at risk of infertility after radiotherapy or chemotherapy and also for preservation of the endangered mammalian species.

Involution dependent changes in distribution and localization of bax, survivin, caspase-3, and calpain-1 in the rat endometrium.

The endometrial layer of the uterus is characterized by continuous cycle of cell growth and apoptosis in response to hormonal changes. Apoptosis is regulated by several apoptotic regulators, but their significance in involuting uterus has not been well understood. For that reason, aim of this study was to investigate possible role of apoptosis-related proteins (bax and survivin) and enzymes (caspase-3 and calpain-1) in the involuting uterus of the rat, using immunohistochemistry. Our results indicated cytoplasmic and nuclear immunostaining for bax, caspase-3, calpain-1 and survivin proteins were found in the endometrial epithelium and stromal cells such as fibroblasts, mast cells and macrophages, and blood vessels; however, calpain-1 immunoreactivity in the endometrial fibroblast was quite weak or absent. Supranuclear punctate bax immunolabelling was also observed in the endometrial fibroblasts and luminal and glandular epithelial cells from days 1st and 3rd following parturition, respectively. Although survivin was localized in the apical cytoplasm underneath the apical membrane of the luminal epithelium on the 1st and 3rd days, it was also localized in the apicolateral membrane and basal cytoplasm on the 10th and 15th days of involution. Immunostainigs demonstrated that expression patterns of all examined proteins varied with structural changes in the luminal epithelium, and number of immunopositive fibroblasts for bax, caspase-3 and survivin increased with advance of postpartum days and reached a maximum on postpartum days 10 and 15. These results suggest that the process of postpartum involution of endometrium may be regulated by apoptotic and non-apoptotic activity of bax, caspase-3, calpain-1, and survivin.

Stem cells and uterine leiomyomas: What is the evidence?

Uterine leiomyomas, also known as uterine fibroids or uterine myomas, are the most common benign gynecologic tumors found in women of reproductive age. In spite of the numerous published studies evaluating the hormonal dependency, epidemiology, molecular biology, pathology, and genetics of leiomyomas, many questions remain unanswered. The remodeling of the uterus in response to hormonal stimuli and its return to a basal state may be related to adult stem/progenitor cells residing in the endometrial and myometrial layers. Recent published papers on stem cells and their paracrine interactions with more specialized cell populations within leiomyomas may help establish the missing link between the development of treatments designed to stop the growth of leiomyomas and therapies devised to eliminate them. Therefore, this study aimed to address the current paradigm regarding the evidence available on the role of stem/progenitor cells in the pathogenesis of uterine leiomyoma. Only a handful of studies involving humans have been published to date describing the presence of somatic stem cells (SSCs) in the myometrium and leiomyomas. No solid conclusion has been established thus far. Despite the fact that these studies strongly pointed to the vital role human leiomyoma stem cells might play in initiating the development of myomas, huge gaps still persist in the literature. Studies to identify putative myometrial and leiomyoma-specific markers might offer new possibilities for understanding the origin of these tumors and perhaps help develop new nonsurgical noninvasive treatments.

Resident Macrophages and Lymphocytes in the Canine Endometrium.

Resident immune cells play a major role in endometrial immunity and in tissue homoeostasis. This study aimed to analyse the distribution of macrophages, B and T lymphocytes (respectively, Mø, B-Lym and T-Lym) in the canine endometrium throughout the oestrous cycle and in late involution (at the proestrus stage post-parturition). An immunohistochemistry technique was used on samples from 50 post-pubertal healthy female dogs, of which five in late post-partum. The distribution of resident immune cells was analysed in three endometrial layers (superficial, intermediate and basal areas). Mø, B-Lym and T-Lym were demonstrated to reside in the endometrium in all the stages of the canine cycle; their numbers being considerably higher during late involution. T-Lym were scattered in the stroma or amidst the glandular epithelium, constituting the predominant immune cell population in anestrus and proestrus, but decreased in number at all other stages. Endometrial B-Lym remained fairly constant during the canine cycle, although its numbers were higher in late involution. Mø counts were higher during anestrus compared to the other stages, the cells being displaced into the superficial endometrial layer. Mø demonstrated the highest level in late involution samples, forming small aggregates below the surface epithelium. The number of immune cells was not normally distributed, suggesting the influence of individual factors, such as age or parity, not explored herein due to limited sample availability. Still, this study provides important information for the interpretation of endometrial biopsies in dogs and for the understanding of the increased susceptibility to uterine infection during dioestrus found in the bitch.

Decidualization and syndecan-1 knock down sensitize endometrial stromal cells to apoptosis induced by embryonic stimuli.

Human embryo invasion and implantation into the inner wall of the maternal uterus, the endometrium, is the pivotal process for a successful pregnancy. Whereas disruption of the endometrial epithelial layer was already correlated with the programmed cell death, the role of apoptosis of the subjacent endometrial stromal cells during implantation is indistinct. The aim was to clarify whether apoptosis plays a role in the stromal invasion and to characterize if the apoptotic susceptibility of endometrial stromal cells to embryonic stimuli is influenced by decidualization and Syndecan-1. Therefore, the immortalized human endometrial stromal cell line St-T1 was used to first generate a new cell line with a stable Syndecan-1 knock down (KdS1), and second to further decidualize the cells with progesterone. As a replacement for the ethically inapplicable embryo all cells were treated with the embryonic factors and secretion products interleukin-1β, interferon-γ, tumor necrosis factor-α, transforming growth factor-β1 and anti-Fas antibody to mimic the embryo contact. Detection of apoptosis was verified via Caspase ELISAs, PARP cleavage and Annexin V staining. Apoptosis-related proteins were investigated via antibody arrays and underlying signaling pathways were analyzed by Western blot. Non-decidualized endometrial stromal cells showed a resistance towards apoptosis which was rescinded by decidualization and Syndecan-1 knock down independent of decidualization. This was correlated with an altered expression of several pro- and anti-apoptotic proteins and connected to a higher activation of pro-survival Akt in non-differentiated St-T1 as an upstream mediator of apoptotis-related proteins. This study provides insight into the largely elusive process of implantation, proposing an important role for stromal cell apoptosis to successfully establish a pregnancy. The impact of Syndecan-1 in attenuating the apoptotic signal is particularly interesting in the light of an already described influence on pregnancy disorders and therefore might provide a useful clinical tool in the future to prevent pregnancy complications provoked by inadequate implantation.