Endometriosis: novel etiopathogenetic concepts and clinical perspectives

MMP-9 as a clinical marker for endometriosis: a meta-analysis and bioinformatics analysis

Aim

This study systematically evaluated the potential efficacy of serum matrix metalloproteinase-9 (MMP-9) concentration as a diagnostic marker for endometriosis through meta-analysis. Early and accurate diagnosis of endometriosis, a common gynecological disease, is crucial for improving patient prognosis. Hence, this study aimed to comprehensively analyze the data from multiple studies to assess the diagnostic value of serum MMP-9 concentration for endometriosis.

Methods

Articles investigating the association between MMP-9 and endometriosis, published from the inception of the databases until February 2024, were systematically retrieved from multiple databases, including PubMed, Embase, Cochrane, Web of Science, Scopus, and CNKI. Download and analyze the GSE7305, GSE23339, and GSE51981 datasets. Statistical analyses of all eligible studies were conducted using RevMan 5.4, Stata 11.0, and R software version 4.3.3.

Results

Fifteen studies fully met the inclusion criteria for the meta-analysis. The concentration of MMP-9 in the blood of patients with endometriosis was significantly higher compared to that of the control group (p < 0.0001). Subgroup analysis based on different stages of endometriosis revealed a trend towards significantly higher serum MMP-9 concentrations in patients, whether in stages I-II or III-IV. Bioinformatics analysis revealed differences in the expression of MMP-9 in endometrial tissue between EMT patients and healthy controls in the GSE7305 and GSE23339 datasets. Additionally, in the GSE51981 dataset, we found significant differences between the normal group and both mild and severe cases of endometriosis.

Conclusion

Both the current meta-analysis and bioinformatics analysis indicate differences in MMP-9 concentration levels between endometriosis patients and healthy individuals, with potentially elevated MMP-9 concentrations in serum samples from patients with endometriosis.

Systematic review registration

https://www.crd.york.ac.uk/prospero, identifier CRD42024525864.

Hidrox® and Endometriosis: Biochemical Evaluation of Oxidative Stress and Pain

Endometriosis is a gynecological and painful condition affecting women of reproductive age. It is characterized by dysfunctional endometrium-like implants outside of the uterine cavity. The purpose of this study was to evaluate the effects of Hidrox®, an aqueous extract of olive pulp containing hydroxytyrosol, on endometriotic lesions associated with pro-oxidative alterations and pain-like behaviors. Endometriosis was induced by intraperitoneal injection of uterine fragments, and Hidrox® was administered daily. At the end of the 14-day treatment, behavioral alterations were assessed and hippocampal tissues were collected. Laparotomy was performed, and the endometrial implants were harvested for histological and biochemical analysis. Hidrox® treatment reduced endometriotic implant area, diameter and volumes. Vehicle-treated rats showed lesional fibrosis, epithelial-mesenchymal transition and fibroblast-myofibroblast transdifferentiation, angiogenesis and pro-oxidative alterations in the peritoneal cavity. Hidrox® treatment reduced the aniline blue-stained area, α-smooth muscle actin (α-sma) and CD34 positive expressions. Moreover, it reduced mast cell recruitment into the lesions, myeloperoxidase activity and lipid peroxidation and increased superoxide dismutase (SOD) activity and glutathione levels in the endometrial explants. In the peritoneal fluid, Hidrox® treatment reduced interleukin (IL)-1β, IL2, IL6, tumor necrosis factor-α (TNF-α) and vascular endothelial grow factor (VEGF) levels increased by the disease. Hidrox® administration also reduced peripheral and visceral sensibility as shown by the behavioral tests (open field test, hot plate test, elevated plus maze test and acetic-acid-induced abdominal contractions). Animals treated with Hidrox® also showed reduced blood-brain barrier permeability and mast cell infiltration in the hippocampus, as well as astrocyte and microglia activation and brain oxidative status restoring brain-derived neurotrophic factor (BDNF) protein expression and increasing Nuclear factor erythroid 2-related factor 2 (Nfr2) nuclear translocation. In conclusion, Hidrox® displayed potential ameliorative effects on endometriotic implants and related pain-induced behaviors due to its potent antioxidative properties.

MiRNA 34-a regulate SIRT-1 and Foxo-1 expression in endometriosis

PURPOSE

The role of the Sirutin 1 (SIRT1) and MicroRNA-34 a (miR-34a) in endometriosis and the extent to which the miR-34a/SIRT1/p53 signaling pathway is involved in its pathogenesis is unclear, so we aimed to investigate the expression of miRNA 34-a, SIRT1, Forkhead boxO (FoxO-1), p53 and other apoptotic markers in endometrial tissue of women with endometriosis in order to better understand their role and the mechanisms of their actions in the pathogenesis of such disease and if it is related to apoptosis or not.

METHODS

Ectopic and eutopic endometriotic tissues were collected from seventy women with endometriosis while normal endometrial tissues were obtained from 40 fertile women without endometriosis and then gene expression of SIRT-1, miR-34a,p53, Bax, Bcl-2, Bcl-xL and FoxO-1 were measured using RT-PCR.

RESULTS

We detected that SIRT-1 and Bcl-xL genes expressions was significantly up-regulated while miRNA34-a,p53, Bax, Bcl-2 and FoxO-1 were down-regulated in endometrial tissue of endometriotic patients compared to that of those without endometriosis. There was an inverse relationship between SIRT-1a, Bcl-xL genes expressions and miR-34a, p53, Bax, Bcl-2 expressions as well as FoxO-1 expression. These results imply that miR-34a might regulate p53 through SIRT-1 and subsequently FoxO-1 expression in endometriotic tissue, and so it can contribute to the pathogenesis of endometriosis by decreasing the naturally occurring apoptosis in endometrium.

CONCLUSION

This study may provide a potential biomarker for endometriosis therapeutics. Identification of target genes downstream of these transcriptional factors would allow better understanding of their respective roles in the pathogenesis of endometriosis.

Endometrial causes of recurrent pregnancy losses: endometriosis, adenomyosis, and chronic endometritis

Chronic inflammatory processes affecting the endometrium, as encountered in endometriosis, adenomyosis, and chronic endometritis, alter endometrial receptivity. These disorders are associated with early pregnancy losses and possibly recurrent pregnancy losses (RPL). In the cases of endometriosis, other factors associated with the disease also are susceptible of causing miscarriages and possibly RPL, such as an impact of intrapelvic inflammatory processes affecting the oocyte and embryo in case of natural conception. Conversely these latter effects obviously are bypassed in case of assisted reproductive technology. Chronic inflammation of the endometrium in the condition known as chronic endometritis also causes early pregnancy losses and RPL with beneficial effects achieved when specific treatment is undertaken.

Novel Drug Targets with Traditional Herbal Medicines for Overcoming Endometriosis

Endometriosis is a disease in which the lining of the endometrium is found outside of the uterus. Recent medical treatments for endometriosis have adverse effects, limiting their long-term use. Furthermore, the recurrence of the disease after the cessation of therapy is quite common, and most patients need to continue treatment to maintain a hypoestrogenic environment till conception. Notwithstanding recent advances in computational and chemical practices, traditional medicines are considered the most consistent sources for the discovery of new drugs. Numerous medicinal plants and plantderived compounds have been tested against gynecological disorders, mainly endometriosis. This review aimed to describe the pharmacological activity profile of the medicinal plants and their active ingredients and draw attention to the discovery of multitargeted drug molecules for rational therapy.

Hepatocyte nuclear factor-1 beta protects endometriotic cells against apoptotic cell death by up-regulating the expression of antiapoptotic genes†

The overexpression of hepatocyte nuclear factor-1 beta (HNF1β) in endometriotic lesion has been demonstrated. However, the role of HNF1β in endometriosis remains largely unknown. Human endometriotic 12Z cells showed higher level of HNF1β when compared with normal endometrial HES cells. In human endometriotic 12Z cells, HNF1β knockdown increased susceptibility to apoptotic cell death by oxidative stress, while HNF1β overexpression suppressed apoptosis. In addition, HNF1β knockdown and overexpression significantly decreased and increased, respectively, the expression of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB)-dependent antiapoptotic genes. Knockdown of the antiapoptotic genes significantly reduced the HNF1β-induced resistance against oxidative stress in 12Z cells. Furthermore, HNF1β regulated the transcriptional activity of NF-κB, and an NF-κB inhibitor suppressed the HNF1β-enhanced NF-κB-dependent antiapoptotic gene expression and the resistance of the 12Z cells against cell death. Taken together, these data suggest that HNF1β overexpression may protect endometriotic cells against oxidative damage by augmenting antiapoptotic gene expression.

Therapeutic Approaches of Resveratrol on Endometriosis via Anti-Inflammatory and Anti-Angiogenic Pathways

Endometriosis represents a severe gynecological pathology, defined by implantation of endometrial glands and stroma outside the uterine cavity. This pathology affects almost 15% of women during reproductive age and has a wide range of consequences. In affected women, infertility has a 30% rate of prevalence and endometriosis implants increase the risk of ovarian cancer. Despite long periods of studies and investigations, the etiology and pathogenesis of this disease still remain not fully understood. Initially, endometriosis was related to retrograde menstruation, but new theories have been launched, suggesting that chronic inflammation can influence the development of endometriosis because inflammatory mediators have been identified elevated in patients with endometriosis, specifically in the peritoneal fluid. The importance of dietary phytochemicals and their effect on different inflammatory diseases have been highlighted, and nowadays more and more studies are focused on the analysis of nutraceuticals. Resveratrol is a phytoestrogen, a natural polyphenolic compound with antiproliferative and anti-inflammatory actions, found in many dietary sources such as grapes, wine, peanuts, soy, berries, and stilbenes. Resveratrol possesses a significant anti-inflammatory effect via inhibition of prostaglandin synthesis and it has been proved that resveratrol can exhibit apoptosis-inducing activities. From the studies reviewed in this paper, it is clear that the anti-inflammatory effect of this natural compound can contribute to the prevention of endometriosis, this phenolic compound now being considered a new innovative drug in the prevention and treatment of this disease.

The Role of Oxidative Stress and Membrane Transport Systems during Endometriosis: A Fresh Look at a Busy Corner

Endometriosis is a condition characterized by the presence of endometrial tissue outside the uterine cavity, leading to a chronic inflammatory reaction. It is one of the most widespread gynecological diseases with a 10-15% prevalence in the general female population, rising up to 30-45% in patients with infertility. Although it was first described in 1860, its etiology and pathogenesis are still unclear. It is now accepted that inflammation plays a central role in the development and progression of endometriosis. In particular, it is marked by an inflammatory process associated with the overproduction of an array of inflammatory mediators such as prostaglandins, metalloproteinases, cytokines, and chemokines. In addition, the growth and adhesion of endometrial cells in the peritoneal cavity due to reactive oxygen species (ROS) and free radicals lead to disease onset, its ensuing symptoms-among which pain and infertility. The aim of our review is to evaluate the role of oxidative stress and ROS in the pathogenesis of endometriosis and the efficacy of antioxidant therapy in the treatment and mitigation of its symptoms.

Back to the Original Question in Endometriosis: Implantation or Metaplasia?

The pathogenesis of some forms of endometriosis is still controversial. Different research approaches have been used to clarify this issue and an intense debate has derived over the years among scientists. This paper presents and discusses aged and modern ideas derived from various observations in different research areas on this specific topic. More specifically, data derived from histological results, animal studies, anatomical findings and basic research activity are presented.

Although an increasing body of evidence tends to support the implantation theory, which currently represents the most recognized pathogenic model for endometriosis, some aspects of this disease remain obscure and the scientific and medical communities have still not made significant progress in terms of completely elucidating the histogenesis of some forms of the disease.

Endometriosis: Aetiopathogenetic Basis

Endometriosis, defined by the presence of endometrial tissue outside the uterine cavity, is a common condition affecting 10% of women in the reproductive age. Menstrual factors reported to increase risk include dysmenorrhea, early menarche, and shorter cycle lengths. The theory of retrograde menstruation with implantation of endometrial fragments, in conjunction with peritoneal factors to stimulate cell growth is the most widely accepted.

There is a growing body of evidence that immunological factors and angiogenesis play a key role in the pathogenesis of endometriosis. In women with endometriosis, there appears to be an alteration in the function of peritoneal macrophages, natural killer cells and lymphocytes, with production of growth factors and inflammatory mediators in the peritoneal fluid. Survival, adhesion, proliferation, invasion and vascularization of endometrial tissue in abdominal cavity may be the consequence of retrograde menstruation and referred to as implantation theory.

Urinary Phytoestrogen Concentrations Are Not Associated with Incident Endometriosis in Premenopausal Women

BACKGROUND

Phytoestrogens have been associated with subtle hormonal changes, but their effects on endometriosis are largely unknown.

OBJECTIVE

We assessed the association between urinary concentrations of phytoestrogens and incident endometriosis.

METHODS

We included an operative sample of 495 premenopausal women aged 18-44 y undergoing laparoscopies and laparotomies at 14 clinical sites between 2007 and 2009 and a general population sample of 131 women from the same geographic area who were matched on age and menstruation status. Endometriosis in the surgical sample was assessed by surgical visualization (clinical gold standard), whereas disease in the general population sample was assessed with the use of a pelvic MRI. Urine concentrations of genistein, daidzen, O-desmethylangolensin, equol, enterodiol, and enterolactone were measured at baseline. Poisson regression with robust error variance was used to estimate the risk of an endometriosis diagnosis for each sample after adjusting for age and body mass index (in kg/m²). Separate models were run for each phytoestrogen.

RESULTS

Overall geometric mean urine concentrations of phytoestrogens were as follows: genistein [88 nmol/L (95% CI: 72, 108 nmol/L)], daidzein [194 nmol/L (95% CI: 160, 236 nmol/L)], O-desmethylangolensin [4 nmol/L (95% CI: 3, 6 nmol/L)], equol [4 nmol/L (95% CI: 4, 6 nmol/L)], enterodiol [29 nmol/L (95% CI: 22, 38 nmol/L)], and enterolactone [355 nmol/L (95% CI: 395, 544 nmol/L)]. Geometric mean concentrations of phytoestrogens did not significantly differ by endometriosis status in either sample. Adjusted RRs for endometriosis ranged from 0.87 to 1.09 for the 6 phytoestrogens measured, with all CIs including a value ≥1. Phytoestrogens were not associated with the severity of endometriosis when restricting the analysis to women with moderate-to-severe disease per the revised American Society for Reproductive Medicine criteria. Furthermore, no associations were observed between self-reported high soy intake and endometriosis.

CONCLUSIONS

Despite endometriosis being an estrogen-dependent disease, we found no evidence that urinary phytoestrogens were associated with a higher risk of an endometriosis diagnosis in either a sample of premenopausal women or in a surgical sample.

The abnormal expression of oxytocin receptors in the uterine junctional zone in women with endometriosis

BACKGROUND

The junctional zone (JZ), also called as the endometrial-myometrial junction, is related to peristaltic-like movements in the non-pregnant uterus. Hyperperistalsis and dysperistalsis of uterus constructions might underlie many important disorders such as dysmenorrhea, infertility, endometriosis, implantation failure. The major proteins for uterine contraction of the non-pregnant uterus may be Oxytocin (OT) and oxytocin receptor (OTR). The objective of this study was to inspect the expression of OTR in isthmic and mid-fundal parts of the uterine junctional zone at different stages of the follicular cycle in patients with and without endometriosis.

METHODS

Uterine biopsies containing endometrium and junctional zone were collected from the isthmic and mid-fundal parts of the anterior wall after hysterectomy. The OTR expression was evaluated by immunohistochemistry.

RESULTS

In the control uterus, OTR expression in the isthmic region was significantly higher than in the fundal region in the proliferative phase (p < 0.05) but significantly lower in the secretory phase (p < 0.05). And the expression of OTR in the proliferative phase was significantly higher than that in the secretory phase in both isthmic and fundal regions (p = 0.000 and 0.049, respectively). However, in endometriosis uteri, OTR expression in the isthmic region showed no significant difference with that in the fundal region in both proliferative and secretory phases (p = 0.597 and 0.736, respectively). In both isthmic and fundal regions, OTR expression was not significantly different between the proliferative phase and secretory phase (p = 0.084 and 0.222, respectively). OTR expression in fundal regions of revised ASRM I and II endometriosis were lower than that of revised ASRM III and IV (p = 0.049). In the fundal region of JZ, the expression of OTR in ovarian endometriosis was significantly lower than that in deep infiltrating endometriosis (p = 0.046). The expression level of OTR in the funds region is positively associated with the severity of dysmenorrhea in endometriosis group (r = 0.870, p < 0.05). Comparing to normal uteri, the expression of OTR in the secretory phase was significantly higher in the endometriosis uteri (p < 0.05). In the fundus of endometriosis uteri, OTR expression was significantly higher in both the proliferative and secretory phases (p = 0.045 and 0.028, respectively).

CONCLUSION

OTR expression in the JZ of women with endometriosis changes significantly, which may result in abnormal uterine contractile activity, reducing the endometriosis-related fertility and dysmenorrhea.

Oxidative Stress Statues in Serum and Follicular Fluid of Women with Endometriosis

OBJECTIVE

This study aimed to evaluate the levels of two oxidative stress (OS) markers including lipid peroxide (LPO) and total antioxidant capacity (TAC) in both serum and follicular fluid (FF) of women with endometriosis after puncture.

MATERIALS AND METHODS

In this cross-sectional study, a total number of sixty-three women younger than 40 years old with laparoscopy (gold standard for endometriosis diagnosis) indication underwent in vitro fertilization (IVF) program in the Royan Institute, Tehran, Iran from September 2013 to October 2014. About forty-three patients were diagnosed with endometriosis after laparoscopy. Blood and FF from the leading follicle in each stimulated ovary were obtained at the time of egg retrieval; samples were centrifuged and frozen until assessment. At the time of sample assessment, serum and FF samples were evaluated for the levels of LPO and TAC on spectrophotometery.

RESULTS

We observed that women with endometriosis had significantly higher LPO and lower TAC levels in the serum and FF as compared with the control group (P<0.05).

CONCLUSION

It has observed that FF of women with endometriosis, regardless of disease stage, increases the proliferation power of endometrial cells in vitro, we presume that inflammatory reactions-induced OS in ovary may be responsible for proliferation induction ability in FF obtained from women with endometriosis.

Selective Estrogen-Receptor Modulators and Aromatase Inhibitors: Promising New Medical Therapies for Endometriosis?

Endometriosis is an estrogen-dependent disease and estrogen-related pathways are imbalanced in women with endometriosis. One of the key enzymes in estrogen synthesis is aromatase. Inhibiting this pathway at several points is a promising idea for the treatment of endometriosis. The third generation of aromatase inhibitors is becoming more potent in efficacy, with fewer side effects than previous generations, but cotreatment with other hormones is needed to inhibit ovarian stimulation. Other components that promote estrogen synthesis such as COX-2 can also be potentially targeted. Selective estrogen-receptor modulators could also be interesting in view of their tissue-specific effect. However, all these new drugs are still in an early phase of development. At present, it is too early to conclude that aromatase inhibitors, COX-2 inhibitors or selective estrogen-receptor modulators really present any added value compared with the existing drugs that can be used to achieve hormonal suppression in the medical treatment of endometriosis.

Effects of cisplatin and letrozole on surgically induced endometriosis and comparison of the two medications in a rat model

This study was to investigate the effects of cisplatin (CDDP) and letrozole on surgically induced endometriosis and comparison of the two drugs in a rat model. Endometriosis was surgically induced by autologous transplantation of endometrial pieces. Thirty model rats were divided into three groups, randomly. Group 1 (n=10) served as control and received no medication. Group 2 (n=10) received 0.2mg/kg/day of oral letrozole. Group 3 (n=10) received 35mg/m(2) CDDP via peritoneal perfusion every four days. All the rats were treated for 24days. The growth and histologic score of the implants were evaluated. The proliferation- and angiogenesis-associated proteins were assessed using immunohistochemistry and western blotting. The serum sex hormones were assayed using ELISA. After the medication, the growth and histologic score of the implants were significantly lower in the 2 and 3 groups than in the control group. The protein expressions of vascular endothelial growth factor (VEGF), aromatase P450 (P450arom), transforming growth factor-beta (TGF-β), and matrix metalloproteinase (MMP)-2, were significantly lower in groups 2 and 3 than in the control group. Further, the P450arom level was lower in the letrozole group than in the CDDP group. The TGF-β and MMP-2 levels were lower in the CDDP group than in the letrozole group. Serum T level was significantly higher in the letrozole group, and serum E2 level was lower in the letrozole group. In conclusion, cisplatin and letrozole caused similar regression of the implants in the endometriosis model rats. But their effects on the proliferation- and angiogenesis-associated protein expressions and the serum sex hormone levels were different. Cisplatin and letrozole might cause the effects in the endometriotic foci through different mechanism.

Endometriosis-associated Malignancy

Endometriosis is a common condition in women of reproductive age. According to several epidemiological studies endometriosis may be associated with increased risk of various malignancies. However, endometriosis-associated malignancy (EAM) is defined by certain histological criteria. About 80 % of EAM have been found in the ovary, whereas 20 % are localized in extragonadal sites like intestine, rectovaginal septum, abdominal wall, pleura and others. Some authors suggest that EAM arise from atypical endometriosis as an intermediate lesion between endometriosis and cancer. Moreover, a number of genetic alterations, like loss of heterozygosity (LOH), PTEN, ARID1 A and p53 mutations have been found in both endometriosis and EAM. Endometriosis-associated ovarian cancer (EAOC) is mostly a well or intermediately differentiated tumor of endometrioid or clear cell histological sub-type. Women affected by EAOC are on average five to ten years younger than non-EAOC patients; in most of the cases EAOC is a low stage disease with favorable clinical outcome. Since EAM is a rare condition systematic data on EAM are still missing. A systematic retrospective study on endometriosis-associated malignancies (EAM study) is currently being conducted by the Endometriosis Research Foundation together with the study groups on ovarian and uterine tumors of the working group for gynecological oncology (AGO) (gyn@mlk-berlin.de).

Immunological aspects of endometriosis: a review

Endometriosis is a common and serious illness affecting women in their reproductive years. Despite the ongoing interest and intensive research of this crippling disease, the cause remains unknown since its first description over 150 years ago. The origins and genesis of endometriosis, despite numerous hypotheses, are still unclear. One of the possible causes of the development of endometriosis might be the immune system, despite the fact that endometriosis is generally considered to be a steroid-sensitive disease. Numerous aspects of the immune system has been found changed, from the different number of activated macrophages to different subtypes of lymphocytes and their activities, suggesting involvement of immunity. On the other hand, it is possible that immunological changes around the endometriotic lesion are only secondary to the establishment of endometriosis. In this review, we will summarize the current knowledge of immunological reactions in endometriosis.

The effect of captopril on endometriotic implants in a rat model

OBJECTIVE

To determine the effects of captopril on experimentally induced endometriosis in a rat model.

STUDY DESIGN

Twenty-four adult, mature female Wistar-Albino rats in which endometriotic implants were induced by transplanting autologous uterine tissue to ectopic sites on the peritoneum. After the endometriotic implants were formed surgically, the 24 rats were randomly divided into three groups. Group 1 (captopril group, eight rats) were given 50 mg kg(-1)d(-1) of oral captopril for 21 d. Group 2 (leuprolide acetate group, eight rats) were given a single 1 mg kg(-1) subcutaneous injection of leuprolide acetate. Group 3 (control) were given no medication and served as controls (eight rats). The surface area of the endometriotic implants and the score of histologic analysis. Also, VEGF and MCP-1 levels in peritoneal fluids and bloods were analyzed.

RESULTS

At the beginning of the medical treatment, the mean surface areas of the endometriotic implants were comparable in all three groups. At the end of the treatment the mean implant surface area in the captopril group and leuprolide acetate group was less than that in the control group. Mean histopathological examination score for the implants post treatment was lower in the captopril and leuprolide acetate groups. Peritoneal fluids VEGF level in the captopril and leuprolide acetate groups was lower than that in the control group. The post-treatment MCP-1 level was also lower in the captopril and leuprolide acetate groups than in the control group. The serum VEGF and MCP-1 levels post treatment were significantly lower in the captopril and leuprolide acetate groups than in the control group.

CONCLUSION

Administration of captopril reduced the size and progression of endometriotic lesions in a rat model.

Atorvastatin exerts anti-nociceptive activity and decreases serum levels of high-sensitivity C-reactive protein and tumor necrosis factor-α in a rat endometriosis model

PURPOSE

The purpose of this study was to examine the effects of atorvastatin in the treatment of experimental endometriosis.

METHODS

Endometriosis was induced in 24 female rats. 4 weeks after the procedure dimensions of the foci were recorded. Rats were divided into three groups: in Group 1 (n = 8), a daily dose of 10 mg/kg atorvastatin was given for 14 days. In the second group (n = 8), a single dose of 1 mg/kg leuprolide acetate was injected intraperitoneally. The rats in Group 3 (n = 8) were received 1 mg/kg i.p. 0.9 % NaCl. At the end of the treatment, laparotomy was performed, and the dimensions of the endometriotic foci were recorded. Biochemical, histopathological and immunohistochemical studies were performed and nociception was compared in groups.

RESULTS

Atorvastatin treatment exhibited significant analgesic activity in hot plate model (P = 0.022). The serum hs-CRP and tumor necrosis TNF-α levels were similar between the Group 2 and Group 3 (P > 0.05); however atorvastatin caused significant decrease in both serum markers. The histological and immunohistochemical scores were also found to be markedly lower in Group 1 and Group 2 (P < 0.05).

CONCLUSION

Atorvastatin treatment may have a therapeutic potential in the treatment of endometriosis through its anti-inflammatory and anti-nociceptive properties.

Role of iron overload-induced macrophage apoptosis in the pathogenesis of peritoneal endometriosis

This article presents an overview of the involvement of iron overload-induced nitric oxide (NO) overproduction in apoptosis of peritoneal macrophages of women with endometriosis. We have postulated that the peritoneal iron overload originated from retrograde menstruation or bleeding lesions in the ectopic endometrium, which may contribute to the development of endometriosis by a wide range of mechanisms, including oxidative damage and chronic inflammation. Excessive NO production may also be associated with impaired clearance of endometrial cells by macrophages, which promotes cell growth in the peritoneal cavity. Therefore, further research of the mechanisms and consequences of macrophage apoptosis in endometriosis helps discover novel therapeutic strategies that are designed to prevent progression of endometriosis.

Endometriosis in a postmenopausal woman on hormonal replacement therapy

Endometriosis is a benign disease and an estrogen-dependent disease. Postmenopausal endometriosis is rare, because the absence of estrogenic hormone production. We report a case of endometriosis presenting in a postmenopausal woman with no history of endometriosis before hormone replacement therapy.

Unravelling the Ovarian Endometrioma Pathogenesis: “The Long and Winding Road” across the Various Theories

Controversy exists regarding the pathogenesis of endometriotic ovarian cysts. Different and complex theories have been proposed over the years since the description of chocolate cysts by Sampson in 1921. We have herein reviewed findings in support and against the most widely accepted theories. According to the theory of Hughesdson and Brosens, a prerequisite for endometrioma formation seems to be the inversion and progressive invagination of the ovarian cortex after the accumulation of menstrual debris derived from bleeding of superficial endometriotic implants, which are located on the ovarian surface and adherent to the peritoneum. Disproving the metaplasia hypothesis put forward by Donnez and coworkers and supporting the involvement of the ovulation process in the development of ovarian endometriosis, Vercellini and colleagues have recently demonstrated that a cystic corpus luteum may be a transitory step toward endometrioma formation. As these theories are not able to explain the various aspects of endometrioma formation fully, the possibility that the coelomic metaplasia of the ovarian mesothelium with changes into typical endometrial glands and stroma might be responsible for the endometrioma formation cannot be totally ruled out. Further research is needed to clearly elucidate the pathogenetic aspects of endometriotic ovarian cysts.

Contraceptive effect of Uncaria tomentosa (cat's claw) in rats with experimental endometriosis

PURPOSE

Evaluate the histological changes in parenchyma's epithelial layer of the uterus and ovarian of rats with induced endometriosis, treated with Uncaria tomentosa extract.

METHODS

29 rats with experimental endometriosis, were selected and divided in three groups: The uncaria group received 32 mg/ml of Uncaria tomentosa extract, 1 ml administered daily and the placebo group received 1 ml of saline 0.9% per day, during for 14 days (both groups); the leuprolide group received leuprolide acetate 1mg/kg body weight applied single subcutaneous dose. In the 15th day of treatment the uterine horn and ovaries were removed for histopathological analysis.

RESULTS

The uncaria group presented nine samples (90%) with immature ovarian follicles, whereas the placebo group did not present any case and in the leuprolide group there were eight rats (88%) with the same change. The placebo group showed mature corpus luteum in all animals, occurring less frequent in uncaria (10%) and leuprolide (22%) groups. The uterine epithelium showed weak proliferative in nine (90%) samples of the uncaria group, in two (20%) animals in the placebo group and seven (77.8%) rats in the leuprolide group.

CONCLUSIONS

The findings suggest that Uncaria tomentosa has contraceptive effect.

A laparoscopic approach to Nuck's duct endometriosis

OBJECTIVE

To report a case of uncommon endometriosis located in the Nuck's duct and its laparoscopic resolution.

DESIGN

Case report.

SETTING

Gynecologic department at 12 de Octubre University Hospital, Madrid.

PATIENT(S)

A 35-year-old woman, gravida 1 para 1, presented with an inguinal right mass. She had a right nephrectomy because of acute pyelonephritis. Computed tomography showed a cystic lesion that was suggestive of a Nuck's duct cyst. Fine-needle aspiration cytology was performed, and endometriosis was determined.

INTERVENTION(S)

Cyst removal and closure of the internal inguinal ring's defect by the laparoscopic approach.

MAIN OUTCOME MEASURE(S)

Disease free.

RESULT(S)

The intervention was successfully performed by laparoscopic approach. The postoperative evolution was good, and the patient was discharged 2 days after surgery.

CONCLUSION(S)

Inguinal or Nuck's duct are both uncommon locations for endometriosis; therefore, it is difficult to suspect in patients without a surgical history. Once identified, the treatment involves removal of the endometrioma and repair of the internal inguinal ring. A laparoscopic approach should be considered when possible.

Endometriosis: associations with menopause, hormone replacement therapy and cancer

Endometriosis is an estrogen-dependent condition and is characterized by the presence of ectopic endometrial tissue. The pathogenesis of this condition remains an enigma. Endometriosis has well known associations with menopause both in terms of secondary outcomes from medical and surgical therapy in premenopausal women, as well as a natural occurrence/recurrence of the disease in women going through menopause naturally. This review article aims to discuss the current day modalities of management of endometriosis with their pros and cons especially in the context of menopause and cancer.

Expression of the human endogenous retroviruse-W envelope gene syncytin in endometriosis lesions

BACKGROUND

None of the existing theories provides a satisfactory explanation of the development of endometriosis. One hypothesis that may lead to further clarification is that the expression of specific proteins of human endogenous retroviruses (HERVs) might influence the development of endometriosis lesions. Such endogenous retroviral proteins include syncytin, coded by HERV-W, which is associated with the physiological development of the placenta during pregnancy. This study investigated the influence of HERV-W gene expression in endometriosis foci (EM) quantitatively at the RNA level.

MATERIALS AND METHODS

Specific RNA expression of syncytin (HERV-W) was investigated in various endometrial tissues from 42 patients (with normal endometrium, postmenopausal endometrium, EM, and endometrial carcinoma). RNA was isolated from the tissue samples and transcribed into DNA using reverse transcriptase polymerase chain reaction. The resulting DNA fragments were analyzed using agarose gel electrophoresis and assessed quantitatively.

RESULTS

Normalized syncytin expression was low in EM. In Histologically normal endometrium from endometriosis patients, the expression of normalized syncytin was seven times higher in comparison with the histologically normal endometrium in the control group.

CONCLUSIONS

HERV-W syncytin expression apparently does not play a role in EM. However, it may possibly influence the development of endometriosis because of increased expression in normal endometrium in endometriosis patients.

Endometriosis: current therapies and new pharmacological developments

Endometriosis is a chronic inflammatory condition that is responsive to management with steroids. The establishment of a steady hormonal environment and inhibition of ovulation can temporarily suppress ectopic implants and reduce inflammation as well as associated pain symptoms. In terms of pharmacological management, the currently available agents are not curative, and treatment often needs to be continued for years or until pregnancy is desired. Similar efficacy has been observed from the various therapies that have been investigated for endometriosis. Accordingly, combined oral contraceptives and progestins, based on their favourable safety profile, tolerability and cost, should be considered as first-line options, as an alternative to surgery and for post-operative adjuvant use. In situations where progestins and oral contraceptives prove ineffective, are poorly tolerated or are contraindicated, gonadotrophin-releasing hormone analogues, danazol or gestrinone may be used. Future therapeutic options for managing endometriosis must compare favourably against existing agents before they can be considered for inclusion into current practice. Finally, as reproductive prognosis is not ameliorated by medical treatment, it is not indicated for women seeking conception.

The cell of origin of ovarian epithelial tumours

Although it is widely believed that ovarian epithelial tumours arise in the coelomic epithelium that covers the ovarian surface, it has been suggested that they could instead arise from tissues that are embryologically derived from the Müllerian ducts. This article revisits this debate by discussing recent epidemiological and molecular biological findings as well as evidence based on histopathological observations of surgical specimens from individuals with familial ovarian cancer predisposition. Morphological, embryological, and molecular biological characteristics of ovarian epithelial tumours that must be accounted for in formulating a theory about their cell of origin are reviewed, followed by comments about the ability of these two hypotheses to account for each of these characteristics. An argument is made that primary ovarian epithelial tumours, fallopian tube carcinomas, and primary peritoneal carcinomas are all Müllerian in nature and could therefore be regarded as a single disease entity. Although a substantial proportion of cancers currently regarded as of primary ovarian origin arise in the fimbriated end of the fallopian tube, this site cannot account for all of these tumours, some of which are most likely derived from components of the secondary Müllerian system.

New drugs in development for the treatment of endometriosis

Endometriosis is a common and enigmatic disease causing pelvic pain and infertility. Current treatment is mainly based on the use of surgery and ovarian suppressive agents. There is in particular the need for new therapeutic options able to allow a normal menstrual cycle to occur and also consent pregnancy. In the present review, we aimed to give a concise and practical overview in order to allow the clinician to clearly understand the level of development of these drugs. We have presented only treatments supported by in vivo researches with a special attention to studies in humans. Results show appealing new possibilities are emerging from agents counteracting the endometriosis-associated inflammation. Recent data also suggests that there is still the opportunity to refine the use of already available agents.

Evaluation of the macroscopic growth degree of experimental endometriosis in rats

PURPOSE

To evaluate macroscopically the growth degree of self-transplantation of endometriosis in rats.

METHODS

Forty female rats, after a 7-day period for adpating and evaluating of the estrous cycle regularity, underwent tail abdominal midline laparotomy with 3-cm cuts. The average third of the left uterine horn was removed, 4mm x 4mm patches in liquid environment were made, and self-transplanted in the rat mesenterium with a single stitch, and the endometrial surface of the endometriotic implant facing the lumen of the peritoneal cavity. The rats were programmed to die after three weeks. The abdominal cavity displaying was held and self-transplants were identified and classified.

RESULTS

The results achieved were: one case for degree 0 (2,5%), three cases for degree 1 (7,5%), eleven cases for degree II (27,5%) and twenty-five cases for degree III (62,5%).

CONCLUSION

The experimental endometriosis development, through the self-transplantation technique, showed to be most common in degrees 3 and 2 of development.

Ablation of leptin signaling disrupts the establishment, development, and maintenance of endometriosis-like lesions in a murine model

Leptin, a 16-kDa cytokine, has been implicated in several reproductive processes and disorders. Notably, elevated leptin levels in the peritoneal fluid of women with mild endometriosis has been demonstrated, suggesting a role for this cytokine in the early stages of disease establishment. To gain insight into the functional significance of leptin during the initial requisite proliferative and neovascularization events involved in endometriosis, we investigated the effect of disruption of in vivo leptin signaling on the establishment and/or maintenance of an endometriosis-like lesion in a syngeneic immunocompetent mouse model of endometriosis. Findings of this study show that the disruption of leptin signaling by ip injection of the pegylated leptin peptide receptor antagonist (LPrA) impairs the establishment of endometriosis-like lesions (derived from uteri of C57BL/6 female siblings) and results in a reduction of viable organized glandular epithelium, vascular endothelial growth factor-A expression, and mitotic activity. LPrA treatment resulted in a significant reduction of microvascular density in endometriosis-like lesions after continuous and acute courses. Endometriosis-like lesions (derived from tissue with functional leptin receptor) of Lepr(db) hosts (nonfunctional leptin receptor) were phenotypically similar to those of LPrA-treated mice. Our results confirm that leptin signaling is a necessary component in lesion proliferation, early vascular recruitment, and maintenance of neoangiogenesis in a murine model of endometriosis.

Agents blocking the nuclear factor-kappaB pathway are effective inhibitors of endometriosis in an in vivo experimental model

BACKGROUND

In vitro studies suggest that the transcription factor nuclear factor-kappa B (NF-kappaB) is implicated in the transduction of proinflammatory signals in endometriosis. The aim of this study was to investigate the involvement of NF-kappaB and the processes regulated by NF-kappaB in the initial development of endometriotic lesionsin vivo.

METHODS

Endometriosis was induced in nude mice by intraperitoneal injection of fluorescent-labeled menstrual endometrium. Two NF-kappaB inhibitors (BAY 11-7085 and SN-50) were injected intraperitoneally on days 0, 2 and 4 after endometriosis induction, and endometriotic lesions were recovered on day 5. Number, mass, fluorimetry and surface (morphometry) of endometriotic lesions were quantified. NF-kappaB activation, intercellular adhesion molecule (ICAM)-1 expression, cell proliferation and apoptosis were evaluated by immunohistochemical analyses and the TUNEL method.

RESULTS

Both NF-kappaB inhibitors induced a significant reduction in lesion development compared to control mice. NF-kappaB activation and ICAM-1 expression of endometriotic lesions were significantly reduced in treated mice, and cell proliferation was significantly reduced in BAY 11-7085-treated mice. Both inhibitors produced a significant increase in apoptosis of endometriotic lesions, as assessed by active caspase-3 immunostaining and the TUNEL method.

CONCLUSION

This study demonstrates, for the first time, that the NF-kappaB pathway is implicated in the development of endometriotic lesions in vivo and that NF-kappaB inhibition reduces ICAM-1 expression and cell proliferation, but increases apoptosis of endometriotic lesions, diminishing the initial development of endometriosis in an animal model.

Hormone-dependent gynaecological disorders: a pathophysiological perspective for appropriate treatment

Hormonal changes are involved in several gynaecological disorders. Correct functioning of the hypothalamus-pituitary-ovarian (HPO) axis is critical for ovulatory function, as well as the growth and differentiation of uterine tissue (myometrium and endometrium). However, the correct functioning of other endocrine glands (thyroid, adrenal cortex, pancreas) is also crucial for correct reproductive function. Genes and environmental factors have an influence on women's fertility through their effect on hormonal function. Consequently, dysfunction of the HPO axis and/or other endocrine systems may cause infertility and gynaecological disorders. The pathogenetic basis can be used to help make the correct clinical decision for treating these diseases. Disturbances related to the menstrual cycle, i.e. amenorrhoea, polycystic ovary syndrome (PCOS) and premenstrual syndrome (PMS), have a close correlation with hypo- or hypersecretion of hormones of the HPO axis. The roles of hypothalamic neurohormones and neurotransmitters in the various forms of amenorrhoea and PMS are well established. PCOS has a complex endocrine/metabolic origin, so a variety of hormonal treatments have been proposed. Hormone derangement has also been proposed as the cause of endometriosis and uterine fibroids. These disorders do not have hyper- or hyposecretion of reproductive hormones, but hyperactivity of oestrogen receptors coupled with a genetic predisposition. The relevance of the endocrine changes is confirmed by the clinical effectiveness of hormonal treatments. In order to establish the correct treatment approach in gynaecological disorders, it is important to understand the endocrine pathophysiology.

Genistein causes regression of endometriotic implants in the rat model

OBJECTIVE

To determine the effects of raloxifene and genistein on experimentally induced endometriosis in a rat model.

DESIGN

Prospective, randomized animal study.

SETTING

Animal surgery laboratory in a university hospital.

ANIMAL(S)

Thirty-three adult, mature female Wistar-Albino rats in which endometriotic implants were induced by transplanting autologous uterine tissue to ectopic sites on the peritoneum.

INTERVENTION(S)

After the endometriotic implants were formed surgically, the 33 rats were randomly divided into three groups. Group 1 (genistein group, 10 rats) were given 500 mg/kg per day of oral genistein. Group 2 (raloxifene group, 10 rats) were given 10 mg/kg per day of oral raloxifene. Group 3 were given no medication and served as controls (13 rats). All the rats continued to receive treatment for 21 days, and then were killed to assess the implants' size and for histologic examination.

MAIN OUTCOME MEASURE(S)

The surface area of the endometriotic implants and the score of histologic analysis.

RESULT(S)

At the beginning of the medical treatment, the mean surface areas of the endometriotic implants were comparable in all three groups. At the end of the medical treatment, the mean surface area of implants in groups 1 and 2 was smaller than that of implants in the control group. The decrease in the surface area of the endometriotic implants was greater in group 1 and group 2 than found in the control group. The histologic assessment revealed that the mean of the histopathologic score of the implants at the end of the treatment was lower in groups 1 and 2 when compared with the control group.

CONCLUSION(S)

Genistein caused a statistically significant regression of endometriotic implants.

Vitamin D reserve is higher in women with endometriosis

BACKGROUND

An immune-mediated defect in recognition and elimination of endometrial fragments refluxed in the peritoneal cavity has been hypothesized to play a crucial role in endometriosis development. Since vitamin D is an effective modulator of the immune system, we have hypothesized that the vitamin D status may have a role in the pathogenesis of endometriosis.

METHODS

Women of reproductive age selected for surgery for gynecological indications were enrolled in this prospective cohort study. Serum levels of 25-hydroxyvitamin-D(3), 1,25-dihydroxyvitamin-D(3) and Ca(2+) were assessed.

RESULTS

Eighty-seven women with endometriosis and 53 controls were recruited. Mean (+/- SD) levels of 25-hydroxyvitamin-D(3) in women with and without endometriosis were 24.9 +/- 14.8 ng/ml and 20.4 +/- 11.8, respectively (P = 0.05). The Odds Ratio (95% Confidence Interval) for endometriosis in patients with levels exceeding the 75th percentile of the serum distribution of the molecule (28.2 ng/ml) was 4.8 (1.7-13.5). A positive gradient according to the severity of the disease was also documented. A trend towards higher levels of 1,25-dihydroxyvitamin-D(3) and Ca(2+) was observed in women with endometriosis, but differences did not reach statistical significance. As expected, serum concentrations of 25-hydroxyvitamin-D(3) and 1,25-dihydroxyvitamin-D(3,) but not Ca(2+), are influenced by the season (P < 0.001, P = 0.004, P = 0.57, respectively), while levels of the three molecules did not vary according to the phase of the menstrual cycle.

CONCLUSIONS

Endometriosis is associated with higher serum levels of vitamin D.