Increased invasion activity of endometrial stromal cells and elevated expression of matrix metalloproteinase messenger RNA in the uterine tissues of mice with experimentally induced adenomyosis

Blockage of the NLRP3 inflammasome by MCC950 inhibits migration and invasion in adenomyosis

RESEARCH QUESTION

Does the NOD-like receptor protein 3 (NLRP3) inflammasome have an effect in adenomyosis?

DESIGN

Fresh-frozen endometrial tissues and paraffin specimens were obtained from endometrial tissues from patients with adenomyosis and controls. Western blot, quantitative real-time polymerase chain reaction (qRT-PCR) and immunohistochemistry (IHC) were applied to assess expression of the NLRP3 inflammasome components. Primary eutopic endometrial stromal cells were isolated from the uteri of patients with adenomyosis. After NLRP3 was knocked down using small interfering RNA, proliferation, invasion and epithelial-mesenchymal transition (EMT) were evaluated using EdU, CCK8, transwell assays and western blot. Importantly, a mouse model of adenomyosis was established to evaluate the effects of the NLRP3 inhibitor MCC950 on the formation of adenomyosis.

RESULTS

Expression of the NLRP3 inflammasome components was elevated in the ectopic or eutopic endometrium of patients with adenomyosis. NLRP3 knockdown inhibited migration, invasion and EMT in endometrial cells and primary endometrial cells (P < 0.0001). MCC950, which blocks the NLRP3 inflammasome, reduced migration and invasion of endometrial cells (P < 0.01) and primary endometrial cells (P < 0.0001) considerably. Importantly, in the mouse model of adenomyosis, MCC950 had a mitigating effect on the severity of adenomyosis (P < 0.01).

CONCLUSIONS

NLRP3 was found to enhance migration, invasion and EMT of human endometrial cells in adenomyosis. Notably, the NLRP3 inhibitor MCC950 reduced migration and invasion of endometrial cells effectively. Furthermore, in the mouse model of adenomyosis, MCC950 exhibited a therapeutic effect by alleviating the severity of adenomyosis.

The Impact of Adenomyosis on Pregnancy

Adenomyosis is characterized by ectopic proliferation of endometrial tissue within the myometrium. Histologically, this condition is marked by the presence of islands of benign endometrial glands surrounded by stromal cells. The myometrium appears thinner, and cross-sectional analysis often reveals signs of recent or chronic hemorrhage. The ectopic endometrial tissue may respond to ovarian hormonal stimulation, exhibiting proliferative or secretory changes during the menstrual cycle, potentially leading to bleeding, uterine swelling, and pain. Adenomyosis can appear as either a diffuse or focal condition. It is crucial to understand that adenomyosis involves the infiltration of the endometrium into the myometrium, rather than its displacement. The surgical management of adenomyosis is contingent upon its anatomical extent. The high incidence of the disease and the myths that develop around it increase the need to study its characteristics and its association with pregnancy and potential obstetric complications. These complications often require quick decisions, appropriate diagnosis, and proper counseling. Therefore, knowing the possible risks associated with adenomyosis is key to decision making. Pregnancy has a positive effect on adenomyosis and its painful symptoms. This improvement is not only due to the inhibition of ovulation, which inhibits the bleeding of adenomyotic tissue, but also to the metabolic, hormonal, immunological, and angiogenic changes associated with pregnancy. Adenomyosis affects pregnancy through disturbances of the endocrine system and the body's immune response at both local and systemic levels. It leads to bleeding from the adenomyotic tissue, molecular and functional abnormalities of the ectopic endometrium, abnormal placentation, and destruction of the adenomyotic tissue due to changes in the hormonal environment that characterizes pregnancy. Some of the obstetric complications that occur in women with adenomyosis in pregnancy include miscarriage, preterm delivery, placenta previa, low birth weight for gestational age, obstetric hemorrhage, and the need for cesarean section. These complications are an understudied field and remain unknown to the majority of obstetricians. These pathological conditions pose challenges to both the typical progression of pregnancy and the smooth conduct of labor in affected women. Further multicenter studies are imperative to validate the most suitable method for concluding labor following surgical intervention for adenomyosis.

Analysis of Membrane Type-1 Matrix Metalloproteinase (MT1-MMP, MMP14) in Eutopic and Ectopic Endometrium and in Serum and Endocervical Mucus of Endometriosis

BACKGROUND

Membrane type-matrix metalloproteinases (MT-MMPs) are a subgroup of the matrix metalloproteinases (MMPs) family and are key molecules in the degradation of the extracellular matrix. Membrane type-1 matrix metalloproteinase (MT1-MMP, MMP14) is often deregulated in different cancer tissues and body fluids of human cancer patients; however, MT1-MMP levels in endometriosis and adenomyosis patients are currently unknown.

MATERIALS AND METHODS

Tissue samples from patients with and without endometriosis or adenomyosis were analyzed with immunohistochemistry for the localization of MT1-MMP. Serum and endocervical mucus samples from patients with and without endometriosis or adenomyosis were investigated with MT1-MMP ELISAs.

RESULTS

MT1-MMP was localized preferentially in the glands of eutopic and ectopic endometrium. MT1-MMP protein levels are significantly reduced in ovarian endometriosis (HSCORE = 31) versus eutopic endometrium (HSCORE = 91) and adenomyosis (HSCORE = 149), but significantly increased in adenomyosis (HSCORE = 149) compared to eutopic endometrium (HSCORE = 91). Similarly, analysis of the levels of MT1-MMP using enzyme-linked immune assays (ELISAs) demonstrated a significant increase in the concentrations of MT1-MMP in the serum of endometriosis patients (1.3 ± 0.8) versus controls (0.7 ± 0.2), but not in the endocervical mucus. Furthermore, MT1-MMP levels in the endocervical mucus of patients with endometriosis were notably reduced in patients using contraception (3.2 ± 0.4) versus those without contraception (3.8 ± 0.2).

CONCLUSIONS

Taken together, our findings showed an opposite regulation of MT1-MMP in the tissue of ovarian endometriosis and adenomyosis compared to eutopic endometrium without endometriosis but increased serum levels in patients with endometriosis.

Pre-clinical models to study abnormal uterine bleeding (AUB)

Abnormal Uterine Bleeding (AUB) is a common debilitating condition that significantly reduces quality of life of women across the reproductive age span. AUB creates significant morbidity, medical, social, and economic problems for women, their families, workplace, and health services. Despite the profoundly negative effects of AUB on public health, advancement in understanding the pathophysiology of AUB and the discovery of novel effective therapies is slow due to lack of reliable pre-clinical models. This review discusses currently available laboratory-based pre-clinical scientific models and how they are used to study AUB. Human and animal in vitro, ex vivo, and in vivo models will be described along with advantages and limitations of each method.

Unveiling the Pathogenesis of Adenomyosis through Animal Models

Background: Adenomyosis is a common gynecological disorder traditionally viewed as “elusive”. Several excellent review papers have been published fairly recently on its pathogenesis, and several theories have been proposed. However, the falsifiability, explanatory power, and predictivity of these theories are often overlooked. Since adenomyosis can occur spontaneously in rodents and many other species, the animal models may help us unveil the pathogenesis of adenomyosis. This review critically tallies experimentally induced models published so far, with a particular focus on their relevance to epidemiological findings, their possible mechanisms of action, and their explanatory and predictive power. Methods: PubMed was exhaustively searched using the phrase “adenomyosis and animal model”, “adenomyosis and experimental model”, “adenomyosis and mouse”, and “adenomyosis and rat”, and the resultant papers were retrieved, carefully read, and the resultant information distilled. All the retrieved papers were then reviewed in a narrative manner. Results: Among all published animal models of adenomyosis, the mouse model of adenomyosis induced by endometrial–myometrial interface disruption (EMID) seems to satisfy the requirements of falsifiability and has the predictive capability and also Hill’s causality criteria. Other theories only partially satisfy Hill’s criteria of causality. In particular, animal models of adenomyosis induced by hyperestrogenism, hyperprolactinemia, or long-term exposure to progestogens without much epidemiological documentation and adenomyosis is usually not the exclusive uterine pathology consequent to those induction procedures. Regardless, uterine disruption appears to be a necessary but not sufficient condition for causing adenomyosis. Conclusions: EMID is, however, unlikely the sole cause for adenomyosis. Future studies, including animal studies, are warranted to understand how and why in utero and/or prenatal exposure to elevated levels of estrogen or estrogenic compounds increases the risk of developing adenomyosis in adulthood, to elucidate whether prolactin plays any role in its pathogenesis, and to identify sufficient condition(s) that cause adenomyosis.

Animal Models of Adenomyosis

Adenomyosis is a nonmalignant uterine disorder in which endometrial tissue exists within and grows into the myometrium. Animal models have generated limited insight into the still-unclear pathogenesis of adenomyosis, provided a platform for preclinical screening of many drugs and compounds with potential as therapeutics, and elucidated mechanisms underlying the pain and fertility issues that occur in many women with the disease. Spontaneous adenomyosis has been studied in nonhuman primates, primarily in the form of case reports. Adenomyosis is routinely experimentally induced in mice through methods such as neonatal tamoxifen exposure, pituitary engraftment, and human tissue xenotransplantation. Several studies have also reported hormonal or environmental toxicant exposures that give rise to murine adenomyosis, and genetically engineered models have been created that recapitulate the human-like condition, most notably involving alteration of β-catenin expression. This review describes the animal models for adenomyosis and their contributions to our understanding of the factors underpinning the development of symptoms. Animal models represent a unique opportunity for understanding the molecular basis of adenomyosis and developing efficacious treatment options for affected women. Herein, we assess their different potentials and limitations with regard to identification of new therapeutic interventions and reflect on future directions for research and drug validation.

Potential mechanisms of an antiadenomyosis chinese herbal formula shaoyao-gancao decoction in primary cell culture model

Background. Shaoyao-Gancao Decoction (SGD), a well-known traditional Chinese medicine prescription, has been widely used to treat adenomyosis, dysmenorrhea, abdominal pain, and inflammation in Asia. However, the mechanism underlying the effectiveness of SGD in the treatment of adenomyosis still remains elusive. The present study aimed to investigate the bioactivity of SGD and its underlying molecular mechanisms using cultured human adenomyosis-derived cells. Methods. Human adenomyosis-derived cells were treated with SGD and its major constituents (paeoniflorin and liquiritin) in vitro. Effects of SGD, paeoniflorin, and liquiritin on cell proliferation and apoptosis were examined by MTT assay and flow cytometry analyses. The effects of SGD, paeoniflorin, and liquiritin on the production of PGE₂ and PGF_2α were assayed using ELISA. ER-α and OTR mRNA expression levels were also evaluated by real-time qRT-PCR. Results. SGD, paeoniflorin, and liquiritin inhibited proliferation and induced apoptosis of human adenomyosis-derived cells in a dose-dependent manner. SGD and paeoniflorin significantly reduced the PGE₂ and PGF_2α production. Furthermore, they remarkably decreased the mRNA levels of ER-α and OTR. Conclusions. The results of this study provide possible mechanisms for the bioactivity of SGD for treating adenomyosis and contribute to the ethnopharmacological knowledge about this prescription.

Differential immunohistochemical expression of matrix metalloproteinase-2 and tissue inhibitor of metalloproteinase-2 in cow uteri with adenomyosis during follicular phase

The present investigation was intended to show a different immunohistochemical profile of matrix metalloproteinase-2 and Tissue inhibitor metalloproteinase-2 in bovine uteri with adenomyosis during follicular phase. Uterine samples of 32 cows in reproductive age were taken from the medial third of one of the uterine horns and grouped according to the adenomyosis degree (superficial and deep). Tissue sections (4 μm) were incubated overnight at 4°C with monoclonal antibody for matrix metalloproteinase-2 and Tissue inhibitor metalloproteinase-2. Staining intensities were evaluated in the luminal epithelium, ectopic and dystopic endometrial tissue (stroma, capillaries and glands), endometrial-myometrial border, myometrium, myometrial vessels (middle tunic and endothelium). The matrix metalloproteinase-2 expression was higher for deep adenomyosis samples, showing a differential mean reactivity in superficial endometrium, myometrial vessels, myometrium adjacent to adenomyotic focus and endometrial-myometrial border (P < 0.05). Moreover, matrix metalloproteinase-2 expression was higher in deep adenomyosis samples than that of Tissue inhibitor metalloproteinase-2 in almost all uterine structures analyzed (except for the endometrial and myometrial vessels and endometrial-myometrial border). The opposite was observed in the follicular phase, for both normal specimens and with superficial adenomyosis, where Tissue inhibitor metalloproteinase-2 expression was higher than that of matrix metalloproteinase-2. In conclusion, a differential pattern of matrix metalloproteinase-2 and Tissue inhibitor metalloproteinase-2 was observed in cow uteri with adenomyosis.

The effects of tamoxifen and estradiol on myometrial differentiation and organization during early uterine development in the CD1 mouse

We used a neonatal mouse model to examine the histogenesis of uterine adenomyosis, and to test whether adenomyosis is due to an abnormality in myometrial differentiation, or in extracellular matrix proteins expression. We also studied the effects of tamoxifen and estradiol on uterine development, myometrial differentiation, and organization. Female CD1 pups were treated with oral tamoxifen (1 mg/kg) (n=27) or estradiol (0.1 mg/kg) (n=24) from age 1 to 5 days. Uteri from control (n=27) and treated mice were obtained on days 2, 5, 10, 15, and 42 of age. We examined the sections histologically, using image analysis and immunohistochemistry for alpha-smooth muscle actin (alpha-SMA), desmin, vimentin, laminin, fibronectin, and estrogen receptor-alpha. Following tamoxifen exposure, all uteri showed adenomyosis by 6 weeks of age (seen as early as day 10). The inner myometrium showed thinning, lack of continuity, disorganization, and bundling. alpha-SMA expression was normal. Desmin expression normally showed a wave of maturation that was absent in tamoxifen-treated mice. In the estradiol group, adenomyosis was not observed. All uterine layers were normally developed, but hypertrophied. The inner myometrium retained its circular arrangement. There was no difference in the localization of laminin or fibronectin between groups (laminin expression was reduced in the tamoxifen treated uteri). Vimentin could not be detected in all groups. Our results suggest that the development of the inner myometrium is particularly sensitive to estrogen antagonism, and can be affected by steroid receptors modulation. Disruption of the inner myometrium may play a role in the development of uterine adenomyosis.

Effects of photodynamic therapy using 5-aminolevulinic acid on cultured human adenomyosis-derived cells

OBJECTIVE

To evaluate the potential of photodynamic therapy with aminolevulinic acid (ALA) on human adenomyosis-derived cells compared with endometrial stromal cells.

DESIGN

In vitro study.

SETTING

Department of Obstetrics and Gynecology, Tohoku University Hospital.

PATIENT(S)

Women with adenomyosis attending the University hospital.

INTERVENTION(S)

Photodynamic treatment.

MAIN OUTCOME MEASURE(S)

Cell survival rates.

RESULT(S)

Treatment with both ALA and irradiation caused significantly decreased survival of cells derived from human adenomyosis compared with ALA or irradiation alone. The combination of irradiation and ALA led to 79.3%, 68.0%, and 59.5% cell survival at 1.6, 4, and 8 J/cm2, respectively, whereas ALA and irradiation alone caused 92.8% and 97% survival, respectively.

CONCLUSION(S)

Photodynamic therapy using ALA caused extensive death of cells derived from human adenomyosis. Photodynamic treatment using ALA may be a new treatment for patients with adenomyosis uteri in the future.

Matrix Metalloproteinase-2 and -9 Expression Correlated with Angiogenesis in Human Adenomyosis

BACKGROUND

Adenomyosis is an important cause of dysmenorrhea and infertility for women all over the world, however, the pathogenesis has not been completely elucidated. The purpose of the study was to investigate the role of matrix metalloproteinases (MMPs) and their relation to angiogenesis in human adenomyosis.

METHODS

Adenomyotic endometrial specimens were removed by hysterectomy from 68 women with adenomyosis. The control group consisted of 26 normal endometrial specimens. Immunohistochemistry was used to demonstrate expression of MMP-2, -9, vascular endothelial growth factor (VEGF) and microvessel density (MVD). Staining intensity was analyzed by computerized image analysis system.

RESULTS

In both eutopic and ectopic endometrium of adenomyosis, the expression of MMP-2, -9 as well as VEGF was significantly greater than in normal endometrium (p < 0.05). MVD was higher in ectopic endometrium than eutopic endometrium with or without adenomyosis (p < 0.05). In adenomyosis, a positive correlation was observed between VEGF expression and MMP-2 (p < 0.001, r = 0.583) as well as MMP-9 expression (p = 0.002,r = 0.490). A positive correlation was also found between MVD and MMP-2 (p < 0.001,r = 0.589) or MMP-9 expression (p < 0.001,r = 0.589).

CONCLUSION

Our results indicate that the elevation of MMP-2, -9 expression may have an important role in the development of adenomyosis, probably through contributing to invasion of endometrial tissues into the myometrium and angiogenesis in adenomyotic implants.

Experimental adenomyosis

Adenomyosis has been reported in a number of different animal species, whereas endometriosis appears limited to humans and non-human primates. This suggests a different aetiology of the two conditions. Adenomyosis develops spontaneously in certain strains of laboratory mice. Its incidence in mice can be markedly enhanced by systemic exposure to various hormonal agents, including prolactin, progesterone, synthetic progestins, certain oestrogenic agents, as well as tamoxifen and toremifene. The precise hormonal changes necessary remain unclear, although the evidence suggests that adenomyosis in this model is not due to a simple oestrogenic effect. Study of the pathological and molecular alterations in this model indicates that disturbances to the uterine stroma, blood vessels and myometrium are also important factors in the development of adenomyosis.

[Adenomyosis: update on a frequent but difficult diagnosis]

Adenomyosis is a frequent entity, with difficult diagnosis, often obtained by pathological analysis performed after hysterectomy. This condition can cause abnormal uterine bleeding and dysmenorrhea, frequent reasons for consultation and hysterectomy. The development of ultrasonographic and magnetic resonance imaging techniques allow preoperative diagnosis. They also permit the use of hysteroscopic techniques for conservative uterine surgery, and have brought diagnosis and management of this disease to the front of the scene. This article reviews the pathological description of the disease, its epidemiology, clinical presentations, useful and necessary explorations, etiopathogeny and available therapies.

Intrinsic form of ureteral endometriosis causing ureteral obstruction and partial loss of kidney function

INTRODUCTION

Urinary tract endometriosis is rare and occurs in about 1% of all endometriotic lesions. About 30% of patients suffer from reduced kidney function at the time of diagnosis.

CASE REPORT

A 49-year-old woman presented with a history of abdominal hysterectomy without adnexae because of uterus myomatosus without any signs of endometriosis 6 years before. Now she complained of dysuria and intermittent left loin pain. Sonography and retrograde pyelography demonstrated incomplete ureteric obstruction and scintigraphy revealed a partial loss of kidney function. Intraoperatively frozen section histology and final histologic examination demonstrated a tumor-like intrinsic form of ureteral endometriosis engulfing the left ureter. The patient was treated with uretero-ureterostomy and danazole for preventing recurrence. She is well 28 months postoperatively.

CONCLUSIONS

In the extrinsic form (about 75% of all cases), ureteral endometriosis is localised to the adventitia or surrounding connective tissue of the ureter, whereas the intrinsic form of ureteral endometriosis is very rare and more often needs aggressive surgery.

Uterine cavity matrix metalloproteinases and cytokines in patients with leiomyoma, adenomyosis or endometrial polyp

OBJECTIVE

To determine whether leiomyoma, adenomyosis and endometrial polyps are associated with changes in uterine cavity matrix metalloproteinases (MMP-2 and MMP-9) and cytokines.

STUDY DESIGN

Uterine cavity irrigation was performed in women with leiomyoma, adenomyosis and endometrial polyps, and in women with a normal uterus. MMP-2 and MMP-9 were assayed in the uterine washings by gelatin zymography. For individual subjects, the total MMP level was obtained by adding the semi-quantitative scores of band densities related to gelatinases in the zymograms. Interleukin-1beta (IL-1beta), tumor necrosis factor-alpha (TNF-alpha), interferon-gamma (IFN-gamma) and transforming growth factor-beta1 (TGF-beta1) were measured using enzyme-linked immunosorbant assay (ELISA) kits.

RESULTS

The uterine cavity of patients with leiomyoma, adenomyosis and endometrial polyps had significantly higher MMP scores than controls. Although the mean IL-1beta levels were elevated in uteri harboring a pathology compared with the normal uteri, the cytokine was significantly elevated only in the adenomyotic group. Significantly elevated levels of IFN-gamma were found in uteri with leiomyoma and endometrial polyps. Uterine washings from leiomyoma and adenomyosis contained significantly elevated mean levels of TGF-beta1 compared with controls, while TNF-alpha was significantly higher only in leiomyoma. When uterine cytokine levels were compared in relation to individual MMP levels a significant relationship was found between TGF-beta1 and elevated levels of MMP-9 and total MMPs in leiomyoma. A significant relationship was also found between IL-1beta and elevated levels of MMP-2, MMP-9 and total MMPs in the endometrial polyp group.

CONCLUSION

The uterine cavity in leiomyoma, adenomyosis and endometrial polyps contains elevated levels of MMPs and cytokines compared with the normal uterus. In some pathologies elevated cytokines are associated with elevated MMPs.

Increase in the number of integrinbeta1-immunoreactive monocyte-lineage cells in experimentally-induced adenomyosis in mice

Uterine adenomyosis is a disease in which hyperplastic endometrial stroma and glands invade the myometrium. We have previously demonstrated that hyperprolactinemia leads to the development of adenomyosis in mice. In the present study, a subtracted cDNA library was made by suppression subtractive hybridization to find specific genes that are abundantly expressed in the adenomyotic but not normal tissue in mice. A cDNA fragment of integrinbeta1 (ibeta1) was found in the library, and the expression of the gene product was increased in the adenomyotic uteri at mRNA and protein levels. Intense ibeta1-immunoreactivity was localized on a group of cells dispersing throughout the endometrial stroma. The number of ibeta1-immunoreactive (ibeta1-ir) cells was significantly greater in the uteri of mice with adenomyosis than normal mice. The majority of the ibeta1-ir cells expressed CD14-ir signal, a marker for monocyte-lineage cells, whereas an increase in the number of CD14-ir cells was also evident in the adenomyotic uteri, especially in the ectopic endometrial tissue. Thus, the adenomyotic stromal tissue contained numerous monocyte-lineage cells with higher expression levels of ibeta1, one of their products. The relationship between the increased number of monocyte-lineage cells and the hyperplastic proliferation of endometrial tissues was discussed with a view to understanding the progressive mechanism of adenomyosis.

Human uterine vascular structures in normal and diseased states

Menstrual bleeding disorders are one of the most common problems presenting to the gynaecologist. There is increasing evidence that alterations in human uterine vascular structures are associated with spontaneous and sex steroid-induced changes in menstrual bleeding patterns. This article will discuss the normal anatomy and physiology of uterine vascular growth, breakdown, and repair and will indicate where altered anatomy and function may contribute to menstrual disorder. In particular, impact of low-dose progestogens on the endometrial vasculature and endometrial vascular fragility will be discussed. Disturbances of myometrial vascular growth and remodeling, including fibroids, adenomyosis, implantation, and arterio-venous malformations will also be addressed.

Adenomyosis

Adenomyosis is characterized as ectopic endometrial tissues within the myometrium in the uterus. The etiology and pathogenetic mechanism(s) responsible for adenomyosis are poorly understood. Definite diagnosis is made on hysterectomy specimens, although attempts are made at securing preoperative diagnosis by magnetic resonance imaging and myometrial biopsies. Definite treatment of symptomatic women is hysterectomy.