Peritoneal cytokines and adhesion formation in endometriosis: an inverse association with vascular endothelial growth factor concentration

Avastin-Loaded 3D-Printed Alginate Scaffold as an Effective Antiadhesive Barrier to Prevent Postsurgical Adhesion Bands Formation

Postoperative adhesion can cause complications, such as pain and organ blockage, in the abdominal regions. To address this issue, surgical techniques and antiadhesive treatments are applied. Given the significant role of vascularization in adhesion band formation, Avastin (Ava) that targets vascular endothelial growth factor (VEGF) can be applied to prevent peritoneal adhesion bands. Moreover, Alginate (Alg), a natural polysaccharide, is a promising physical barrier to prevent adhesion bands. Incorporating Ava into Alg hydrogel in a form of 3D-printed scaffold (Alg/Ava) has potential to suppress inflammation and angiogenesis, leading to reduce peritoneal adhesion bands. Following physical, morphological, and biocompatibility evaluations, the efficacy of Alg and Ava alone and their combination in Alg/Ava on the formation of postsurgical adhesions is evaluated. Upon confirming physical stability and sustained release of Ava, the Alg/Ava scaffold effectively diminishes both the extent and strength of adhesion bands. Histopathological examination shows that the reduction in fibrosis and inflammation is responsible for preventing adhesion bands by the Alg/Ava scaffold. Additionally, the cytokine assessment reveals that this is due to the inhibition in the secretion of VEGF and Interleukin 6 suppressing vascularization and inflammatory pathways. This study suggests that a 3D-printed Alg/Ava scaffold has great potential to prevent the postsurgical adhesion bands.

Analysis of VEGF, IGF1/2 and the Long Noncoding RNA (lncRNA) H19 Expression in Polish Women with Endometriosis

The coordinated action of VEGF, IGF1/2 and H19 factors influences the development of endometriosis. The aim of this study was to analyze the expression level of these genes in patients with endometriosis. The study group consisted of 100 patients who were diagnosed with endometriosis on laparoscopic and pathological examination. The control group consisted of 100 patients who were found to be free of endometriosis during the surgical procedure and whose eutopic endometrium wasnormal on histopathological examination. These patients were operated on for uterine fibroids. Gene expression was determined by RT-PCR. The expression of the VEGF gene was significantly higher in the samples classified as clinical stage 1-2 compared to the control material (p < 0.05). There was also a statistically significant difference between the samples studied at clinical stages 1-2 and 3-4 (p < 0.01). The expression of the VEGF gene in the group classified as 1-2 was significantly higher. IGF1 gene expression was significantly lower both in the group of samples classified as clinical stages 1-2 and 3-4 compared to the control group (p < 0.05 in both cases). The expression of the H19 gene was significantly lower in the group of samples classified as clinical stage 3-4 compared to the control group (p < 0.01). The reported studies suggest significant roles of VEGF, IGF and H19 expression in the pathogenesis of endometriosis.

Immune pathway through endometriosis to ovarian cancer

Endometriosis is an estrogen-dependent inflammatory disease, defined by the presence of functional endometrial tissue outside of the uterine cavity. This disease is one of the main gynecological diseases, affecting around 10%-15% women and girls of reproductive age, being a common gynecologic disorder. Although endometriosis is a benign disease, it shares several characteristics with invasive cancer. Studies support that it has been linked with an increased chance of developing endometrial ovarian cancer, representing an earlier stage of neoplastic processes. This is particularly true for women with clear cell carcinoma, low-grade serous carcinoma and endometrioid. However, the carcinogenic pathways between both pathologies remain poorly understood. Current studies suggest a connection between endometriosis and endometriosis-associated ovarian cancers (EAOCs) via pathways associated with oxidative stress, inflammation, and hyperestrogenism. This article aims to review current data on the molecular events linked to the development of EAOCs from endometriosis, specifically focusing on the complex relationship between the immune response to endometriosis and cancer, including the molecular mechanisms and their ramifications. Examining recent developments in immunotherapy and their potential to boost the effectiveness of future treatments.

IL-8 and IL-12p70 are associated with pelvic pain among infertile women with endometriosis

OBJECTIVE

To evaluate interleukin (IL)-1β, IL-6, IL-8, and IL-12p70 levels in serum and peritoneal fluid in women related to infertility and pelvic pain.

METHODS

Eighty-seven women were diagnosed with endometriosis or cases related to infertility. IL-1β, IL-6, IL-8, and IL-12p70 levels in serum and peritoneal fluid were determined by enzyme-linked immunosorbent assay (ELISA). Pain assessment was evaluated by the Visual Analog Scale (VAS) score.

RESULTS

Serum IL-6 and IL-12p70 levels increased in women with endometriosis compared to the control group. Serum and peritoneal IL-8 and IL-12p70 levels correlated with VAS scores in infertile women. A positive correlation was also found between peritoneal IL-1β and IL-6 with VAS score. A significant difference in peritoneal IL-1β levels was associated with menstrual pelvic pain, while peritoneal IL-8 levels were related to dyspareunia, menstrual, and post-menstrual pelvic pain in infertile women.

CONCLUSIONS

An association of IL-8 and IL-12p70 levels were related to pain in endometriosis, as well as a relationship between cytokine expression and VAS score. Further studies should be addressed to investigate the precise mechanism of cytokine-related pain in endometriosis.

Sphingosine 1-phosphate elicits a ROS-mediated proinflammatory response in human endometrial stromal cells via ERK5 activation

Endometriosis is a chronic gynecological disease affecting ~10% women in the reproductive age characterized by the growth of endometrial glands and stroma outside the uterine cavity. The inflammatory process has a key role in the initiation and progression of the disorder. Currently, there are no available early diagnostic tests and therapy relies exclusively on symptomatic drugs, so that elucidation of the complex molecular mechanisms involved in the pathogenesis of endometriosis is an unmet need. The signaling of the bioactive sphingolipid sphingosine 1-phosphate (S1P) is deeply dysregulated in endometriosis. S1P modulates a variety of fundamental cellular processes, including inflammation, neo-angiogenesis, and immune responses acting mainly as ligand of a family of G-protein-coupled receptors named S1P receptors (S1PR), S1P1-5 . Here, we demonstrated that the mitogen-activated protein kinase ERK5, that is expressed in endometriotic lesions as determined by quantitative PCR, is activated by S1P in human endometrial stromal cells. S1P-induced ERK5 activation was shown to be triggered by S1P1/3 receptors via a SFK/MEK5-dependent axis. S1P-induced ERK5 activation was, in turn, responsible for the increase of reactive oxygen species and proinflammatory cytokine expression in human endometrial stromal cells. The present findings indicate that the S1P signaling, via ERK5 activation, supports a proinflammatory response in the endometrium and establish the rationale for the exploitation of innovative therapeutic targets for endometriosis.

Peritoneal immune microenvironment of endometriosis: Role and therapeutic perspectives

Endometriosis, an estrogen-dependent chronic inflammatory disease characterized by the growth of endometrium-like tissues outside the uterine cavity, affects 10% of reproductive-age women. Although the pathogenesis of endometriosis is uncertain, it is widely accepted that retrograde menstruation results in ectopic endometrial tissue implantation. Given that not all women with retrograde menstruation develop endometriosis, immune factors have been hypothesized to affect the pathogenesis of endometriosis. In this review, we demonstrate that the peritoneal immune microenvironment, including innate immunity and adaptive immunity, plays a central role in the pathogenesis of endometriosis. Current evidence supports the fact that immune cells, such as macrophages, natural killer (NK) cells, dendritic cells (DCs), neutrophils, T cells, and B cells, as well as cytokines and inflammatory mediators, contribute to the vascularization and fibrogenesis of endometriotic lesions, accelerating the implantation and development of ectopic endometrial lesions. Endocrine system dysfunction influences the immune microenvironment through overexpressed estrogen and progesterone resistance. In light of the limitations of hormonal therapy, we describe the prospects for potential diagnostic biomarkers and nonhormonal therapy based on the regulation of the immune microenvironment. Further studies are warranted to explore the available diagnostic biomarkers and immunological therapeutic strategies for endometriosis.

Molecular and Biochemical Mechanism of Cannabidiol in the Management of the Inflammatory and Oxidative Processes Associated with Endometriosis

Endometriosis is usually associated with inflammation and chronic pelvic pain. This paper focuses the attention on the anti-inflammatory, anti-oxidant and analgesic effects of cannabidiol (CBD) and on its potential role in endometriosis. We employed an in vivo model of endometriosis and administered CBD daily by gavage. CBD administration strongly reduced lesions diameter, volume and area. In particular, it was able to modify lesion morphology, reducing epithelial glands and stroma. CBD showed anti-oxidant effects reducing lipid peroxidation, the expression of Nox-1 and Nox-4 enzymes. CBD restored the oxidative equilibrium of the endogenous cellular defense as showed by the SOD activity and the GSH levels in the lesions. CBD also showed important antifibrotic effects as showed by the Masson trichrome staining and by downregulated expression of MMP-9, iNOS and TGF-β. CBD was able to reduce inflammation both in the harvested lesions, as showed by the increased Ikb-α and reduced COX2 cytosolic expressions and reduced NFkB nuclear localization, and in the peritoneal fluids as showed by the decreased TNF-α, PGE2 and IL-1α levels. CBD has important analgesic effects as showed by the reduced mast cells recruitment in the spinal cord and the reduced release of neuro-sensitizing and pro-inflammatory mediators. In conclusion, the collected data showed that CBD has an effective and coordinated effects in endometriosis suppression.

Metformin as a Potential Treatment Option for Endometriosis

Endometriosis is a common disease in women of reproductive age, and its pathogenesis seems to be largely affected by hormone imbalance, inflammation, oxidative stress, and autophagy dysregulation. These pathophysiological disturbances interact with one another through mechanisms that are still awaiting elucidation. The aim of this article is to present current knowledge regarding the possibilities of using metformin in the pharmacological treatment of endometriosis. Metformin is an insulin sensitizer widely used for the treatment of type 2 diabetes mellitus. The pleiotropic effects of metformin are mainly exerted through the activation of AMP-activated protein kinase, which is the key cellular energy homeostasis regulator that inhibits mTOR, a major autophagy suppressor. Metformin regresses endometriotic implants by increasing the activity of superoxide dismutase. It is also an inhibitor of metalloproteinase-2, decreasing the levels of the vascular endothelial growth factor and matrix metalloproteinase-9 in animal studies. In endometriosis, metformin might modify the stroma-epithelium communication via Wnt2/β-catenin. With its unique therapeutic mechanisms and no serious side effects, metformin seems to be a helpful anti-inflammatory and anti-proliferative agent in the treatment of endometriosis. It could be a missing link for the successful treatment of this chronic disease.

Adipose tissue-derived mesenchymal stem cells reduce endometriosis cellular proliferation through their anti-inflammatory effects

Objective

Endometriosis is a chronic debilitating inflammatory condition characterized by the presence of endometrial tissues outside the uterine cavity. Pelvic soreness and infertility are the usual association. Due to the poor effectiveness of the hormone therapy and the high incidence of recurrence following surgical excision, there is no single effective option for management of endometriosis. Mesenchymal stem cells (MSCs) are multipotent stromal cells studied for their broad immunoregulatory and anti-inflammatory properties; however, their efficiency in endometriosis cases is still a controversial issue. Our study aim was to evaluate whether adipose tissue-derived MSCs (AD-MSCs) could help with endometriosis through their studied anti-inflammatory role.

Methods

Female Wistar rats weighting 180 to 250 g were randomly divided into two groups: group 1, endometriosis group; established by transplanting autologous uterine tissue into rats’ peritoneal cavities and group 2, stem cell treated group; treated with AD-MSCs on the 5th day after induction of endometriosis. The proliferative activity of the endometriosis lesions was evaluated through Ki67 staining. Quantitative estimation of interferon γ, tumor necrosis factor-α, interleukin (IL)-6, IL-1β, IL-10, and transforming growth factor β expression, as well as immunohistochemical detection of CD68 positive macrophages, were used to assess the inflammatory status.

Results

The size and proliferative activity of endometriosis lesions were significantly reduced in the stem cell treated group. Stem cells efficiently mitigated endometriosis associated chronic inflammatory reactions estimated through reduction of CD68 positive macrophages and the expression of the proinflammatory cytokines.

Conclusion

Stem cell therapy can be considered a novel remedy in endometriosis possibly through its anti-inflammatory and antiproliferative properties.

Analysis on clinical association of uterine scar diverticulum with subsequent infertility in patients underwent cesarean section

To evaluate the relationship between uterine cesarean scar diverticulum (CSD) and subsequent infertility in patients who underwent cesarean section, and determine the effects of pelvic fluid-releasing inflammations on infertility.A retrospective analysis was designed among patients with CSD who were admitted to our hospital from January 1, 2018 to December 31, 2019. A total of 60 patients with CSD and uterine fibroids or benign ovarian tumors who underwent cesarean section were included, and divided into the CSD group and control group. Baseline characteristics of all patients were collected, and the pelvic adhesion scores and the percents of tubal patency were evaluated. Furthermore, the postoperative clinical outcomes were followed up. The levels of inflammatory factors in pelvic fluid were tested using Elisa kits.Preoperative data indicated that the size of the uterine scar diverticulum was (1.68 ± 0.52) cm, the pelvic adhesion scores were higher in CSD group than control group (4.67 ± 0.90 vs 0.47 ± 0.90, P < .05), and 21 of 30 patients with unobstructed fallopian tubes. The levels of tumor necrosis factor-α, interleukin-1β, and interleukin-6 in patients with CSD were obviously higher than control group (P < .05). After the follow-up, the data displayed that no CSD was found in all patients, the time of menstrual period in patients with CSD was shortened to 7.80 ± 1.27 days, and the myometrial thickness at uterine scar was significantly increased (P < .05). Additionally, the pregnancy rate was increased, and 12 of 30 patients were repregnant. Correlation analysis showed that the levels of inflammatory factors (tumor necrosis factor-α, interleukin-1β, interleukin-6), the size of uterine scar diverticulum, and the myometrial thickness at uterine scar were significantly correlated with subsequent infertility (r = 0.307, 0.083, 0.147, 0.405, 0.291, P < .05).Uterine scar diverticulum repair could improve menstrual prolongation, increased the thickness of myometrium and repregnant rate. Subsequent infertility was positively correlated with uterine scar diverticulum and the levels of inflammatory factors.

Endometriotic Peritoneal Fluid Stimulates Recruitment of CD4+CD25highFOXP3+ Treg Cells

Endometriosis is a common gynecological disorder characterized by the presence of endometrial-like tissue outside the uterus. The disease is associated with disturbed local and systemic immunity. It has been reported that the proportion of CD4⁺CD25^highFOXP3⁺ Treg cells may be significantly increased in the peritoneal fluid of patients with endometriosis. Therefore, the aim of our study was to investigate whether the proportions of Treg cells in the peritoneal cavity of patients with endometriosis are related to the chemotactic and stimulatory activity of the local peritoneal milieu. The peritoneal fluid was collected from 13 women with ovarian endometriosis and 12 control women without the disease. T cell populations were analyzed by flow cytometry, cytokines and chemokines were evaluated using the cytometric bead kit, and cell chemotaxis was studied by cell migration assay. We confirmed that the proportions of Treg cells are increased in the peritoneal fluid of women with endometriosis as compared to the control women. Endometriosis was also associated with elevated concentrations of IL-6, IL-10, and TGF-β1/2 as well as CCL20, CXCL8, CXCL9, and CXCL10. We did not reveal any changes in the proportion of peritoneal Th17 cells and concentrations of IL-17A. Peritoneal Treg cells positively correlated with concentrations of TGF-β, IL-10, and CCL20. Endometriotic peritoneal fluid stimulated chemotaxis of both CD4⁺ and Treg cells. This chemotactic activity positively correlated with concentrations of CCL20. CCL20 stimulated the migration of Treg cells, and the chemotactic activity of the endometriotic peritoneal fluid was inhibited by neutralizing anti-CCL20 antibodies. These results imply that increased proportions of the peritoneal Treg cells in women with endometriosis may result from attraction and activation by local chemokines and cytokines, especially CCL20 and TGF-β. Since Treg cells contribute to the immunopathogenesis of endometriosis, their chemotaxis and activation may be considered as a target for therapeutic intervention.

Peritoneal Fluid from Patients with Ovarian Endometriosis Displays Immunosuppressive Potential and Stimulates Th2 Response

Endometriosis is a common gynaecological disorder characterized by the ectopic growth of endometrial tissue outside the uterine cavity. It is associated with chronic pelvic inflammation and autoimmune reactivity manifesting by autoantibody production and abrogated cellular immune responses. Endometriotic peritoneal fluid contains various infiltrating leucocyte populations and a bulk of proinflammatory and immunoregulatory cytokines. However, the nature and significance of the peritoneal milieu in women with endometriosis still remains obscure. Therefore, the aim of the present study was to investigate the immunoregulatory activity of the peritoneal fluid (PF) from women with endometriosis. The peritoneal fluid samples were collected during laparoscopic surgery from 30 women with and without endometriosis. Immunoregulatory cytokines (IL-2, IL-4, IL-6, IL-10, IL-17A, IFN-γ and TNF) and chemokines (CCL2, CCL5, CXCL8 and CXCL9) were evaluated in PF and culture supernatants generated by unstimulated and CD3/CD28/IL-2-stimulated CD4⁺ T cells cultured in the presence of PF. The effect of PF on the generation of Treg and Th17 cells in CD4⁺ T cell cultures, as well as the natural cytotoxic activity of peripheral blood mononuclear cells, was also investigated. Concentrations of IL-6, IL-10, CCL2, CXCL8 and CXCL9 were significantly upregulated in the PF from women with endometriosis when compared to control women, whereas concentrations of other cytokines and chemokines were unaffected. The culturing of unstimulated and CD3/CD28/IL-2-stimulated CD4⁺ T cells in the presence of endometriotic PF resulted in the downregulation of their IL-2, IFN-γ, IL-17A and TNF production as compared to culture medium alone. On the other side, endometriotic PF significantly stimulated the production of IL-4 and IL-10. Endometriotic PF also stimulated the release of CCL2 and CXCL8, whereas the production of CCL5 and CXCL9 was downregulated. Endometriotic PF stimulated the generation of Treg cells and had an inhibitory effect on the generation of Th17 cells in cultures of CD4⁺ T cells. It also inhibited the NK cell cytotoxic activity of the peripheral blood lymphocytes. These results strongly imply that the PF from patients with endometriosis has immunoregulatory/immunosuppressive activity and shifts the Th1/Th2 cytokine balance toward the Th2 response, which may account for deviation of local and systemic immune responses. However, a similar trend, albeit not a statistically significant one, was also observed in case of PF from women without endometriosis, thus suggesting that peritoneal milieu may in general display some immunoregulatory/immunosuppressive properties. It should be stressed, however, that our present observations were made on a relatively small number of PF samples and further studies are needed to reveal possible mechanism(s) responsible for this phenomenon.

Network Pharmacology-Based Prediction of Bioactive Compounds and Potential Targets of Wenjing Decoction for Treatment of Endometriosis

Endometriosis is a chronic estrogen-dependent inflammatory disorder that negatively affects the quality of life in women. The Wenjing decoction (WJD) is a traditional Chinese medicine that has been shown to have a therapeutic effect on endometriosis. Our study systematically explored the mechanism of WJD against endometriosis using a network pharmacology approach. Potentially bioactive compounds of WJD and their possible targets were retrieved from the Traditional Chinese Medicine System Pharmacology Database and Analysis Platform. The protein-protein interaction network and herbs-compounds-genes multinetwork were constructed using Cytoscape for visualization. Subsequently, the signaling pathways of common targets were retrieved from the Kyoto Encyclopedia of Genes and Genomes (KEGG) databases, and molecular docking was performed using PyRx software. In total, 48 common targets were screened, such as IL6 and ESR1, which were related to inflammation and the endocrine system. The top five bioactive compounds were quercetin, kaempferol, wogonin, beta-sitosterol, and stigmasterol. KEGG enrichment analysis revealed 65 pathways containing inflammatory- and endocrine-related signaling pathways, such as the "TNF signaling pathway" and the "estrogen signaling pathway." Taken together, the results of our network pharmacology analysis predicted that certain active ingredients of WJD might treat endometriosis by regulating inflammation and/or endocrine, which provided references for further understanding and exploration of WJD on endometriosis.

PPARγ Agonists: Emergent Therapy in Endometriosis

Endometriosis is one of the major gynecological diseases of reproductive-age women. This disease is characterized by the presence of glands and stroma outside the uterine cavity. Several studies have shown the major role of inflammation, angiogenesis, adhesion and invasion, and apoptosis in endometriotic lesions. Nevertheless, the mechanisms underlying endometriotic mechanisms still remain unclear and therapies are not currently efficient. The introduction of new agents can be effective by improving the condition of patients. PPARγ ligands can directly modulate these pathways in endometriosis. However, data in humans remain low. Thus, the purpose of this review is to summarize the potential actions of PPARγ agonists in endometriosis by acting on inflammation, angiogenesis, invasion, adhesion, and apoptosis.

Role of adipokines in the ovarian function: Oogenesis and steroidogenesis

Adipokines are mainly produced by adipose tissue; however, their expression has been reported in other organs including female reproductive tissues. Therefore, adipokines have opened new avenues of research in female fertility. In this regard, studies reported different roles for certain adipokines in ovarian function, although the role of other recently identified adipokines is still controversial. It seems that adipokines are essential for normal ovarian function and their abnormal levels could be associated with ovarian-related disorders. The objective of this study is to review the available information regarding the role of adipokines in ovarian functions including follicular development, oogenesis and steroidogenesis and also their involvement in ovary-related disorders.

Features of local immunity in women with endometriosis and genital infection

Introduction. External genital endometriosis is an inflammatory estrogen-dependent disease characterized by implantation and proliferation of endometrial tissue outside the uterus, accompanied by increased production of proinflammatory cytokines, prostaglandins, components of the complement, hydrolytic enzymes, increased angiogenesis and anomalies of ectopic endometrium. According to implantation theory, external genital endometriosis develops from viable endometrial cells transferred retrogradely through the fallopian tubes to the abdominal cavity during menstruation, while a disturbed local immunity is an important factor in its pathogenesis. Genital pathogens may be involved in the formation of the immune environment of the peritoneal cavity in women with endometriosis.Purpose. To study the peculiarities of local immunity in women with external genital endometriosis and genital infection pathogens.Materials and methods. 159 women with external genital endometriosis were examined. The total number of leukocytes, the absolute and relative number of viable cells, counts of neutrophils, macrophages and their functional activity, the level of IL-2, IL-4, IL-6, IL-8, IL-10, IL-12, IFNα, IFNγ, TNFα in the peritoneal fluid were evaluated. The study of local immunity was performed in women with endometriosis, stage 1—2 and 3—4, depending on detected genital pathogens. Chlamydia trachomatis, Ureaplasma spp., Mycoplasma genitalium, HSV1,2/CMV, high carcinogenic risk HPV were analyzed by using PCR in samples collected from the endometrium, peritoneal fluid, and endometrioid heterotopies. Statistical processing was performed by using the IBM SPSS Statistics Version 22.2 statistical analysis software package.Results. In the presence of HPV and Ureaplasma spp. in women with endometriosis, stage 1—2, the decreased functional activity of peritoneal neutrophils and macrophages was found. At 3—4 stage, a correlation analysis revealed that detected HPV and Ureaplasma spp. obtained increased both pro-inflammatory and anti-inflammatory cytokines in the peritoneum. However, the higher activity of Th-2 cells in the peritoneal fluid secreting IL-4 and IL-10 and suppressing cellular immunity, was observed in HPV-positive samples. In addition, HPV also correlated with a decreased IL-2 and IL-4 levels.Conclusions. The most prominent changes in the immunological parameters from peritoneal fluid samples were observed in case of detected genital infection pathogens, particularly HPV. Thus, immune disturbances emerged upon bacterial and viral pathogen detection may contribute to the implantation of endometrial cells in the pelvic organs and disease progression.

Curcumin and Endometriosis

Endometriosis is one of the main common gynecological disorders, which is characterized by the presence of glands and stroma outside the uterine cavity. Some findings have highlighted the main role of inflammation in endometriosis by acting on proliferation, apoptosis and angiogenesis. Oxidative stress, an imbalance between reactive oxygen species and antioxidants, could have a key role in the initiation and progression of endometriosis by resulting in inflammatory responses in the peritoneal cavity. Nevertheless, the mechanisms underlying this disease are still unclear and therapies are not currently efficient. Curcumin is a major anti-inflammatory agent. Several findings have highlighted the anti-oxidant, anti-inflammatory and anti-angiogenic properties of curcumin. The purpose of this review is to summarize the potential action of curcumin in endometriosis by acting on inflammation, oxidative stress, invasion and adhesion, apoptosis and angiogenesis.

Cellular Components Contributing to Fibrosis in Endometriosis: A Literature Review

Endometriosis-related fibrosis represents a complex phenomenon with underlying mechanisms yet to be clarified. Fibrosis is consistently present in all disease forms and contributes to classic endometriosis-related symptoms of pain and infertility. The purpose of this literature review was to examine the role of various cellular populations and biologic mechanisms and signaling pathways in inducing fibrogenesis of endometriotic lesions. A search was performed through PubMed and MEDLINE for animal and human studies published in English in the last 23 years that examined fibrosis in superficial, ovarian, and deep infiltrating endometriosis. The main cell types found to be involved in the development of fibrosis were platelets, macrophages, ectopic endometrial cells, and sensory nerve fibers. Interactions among each of the cell types contribute to the production of fibrosis through the production of soluble factors, mostly transforming growth factor-β but also other cytokines and neuropeptides. Cell types known to be critical to the pathophysiology of endometriosis also contribute to fibrogenesis, thus supporting the theory that fibrosis is an inherent part of endometriosis.

Ureaplasma Urealyticum Infection Contributes to the Development of Pelvic Endometriosis Through Toll-Like Receptor 2

Endometriosis is a chronic gynecological disorder, characterized by the presence of ectopic endometrial tissue outside the uterine cavity. Among several hypotheses, Sampson's theory of retrograde menstruation is still applicable. Recent studies have reported the importance of inflammation among endometrial tissue, the peritoneum, and immune cells. However, less is known regarding the role of bacterial infection in the pathophysiology of endometriosis. We hypothesized that Ureaplasma urealyticum infection might contribute to the development of endometriosis by inducing the production of inflammatory mediators by peritoneal mesothelial cells (PMCs), possibly through TLR2. Hence, our objective was to reveal whether PMC infection by U. urealyticum is associated with endometriosis. Moreover, we aimed to demonstrate the molecular mechanism involved in this relationship. We developed a new infection-induced mouse model of endometriosis with wild type and Tlr2-deficient mice. Based on the in vivo mouse model, U. urealyticum-infected mice showed significantly increased numbers and sizes of ectopic endometriotic lesions. U. urealyticum upregulated not only the production of IL-6, CXCL1, and CCL2, but also the expression of ICAM-1, VCAM-1, and MMP2 in murine PMCs. Similarly, endometrial stromal cells dose-dependently produced IL-6, CXCL1, and CCL2 in response to U. urealyticum infection. The series of inflammatory responses in PMCs was mediated mainly through TLR2. The phosphorylation of ERK and JNK was observed when U. urealyticum was added to PMCs and knock out of Tlr2 inhibited these MAPKs phosphorylation. Based on our co-culture study, U. urealyticum-infected PMCs exhibited significantly increased attachment to ESCs compared with uninfected PMCs. Collectively, U. urealyticum infection promotes the development of endometriosis by increasing inflammatory mediators, adhesion molecules, and MMP-2 expression in PMCs through TLR2 signaling. Through our results, we present a theory that infection-induced pelvic inflammation contributes to the initiation and progression of endometriosis. Appropriate treatment of reproductive tract infection may decrease the prevalence of endometriosis.

The role of inflammation, oxidative stress, angiogenesis, and apoptosis in the pathophysiology of endometriosis: Basic science and new insights based on gene expression

Endometriosis is a frequent and chronic illness in young women which could be defined by the existence of endometrial stroma and glands outside of the normal site of the lining of the uterus. It has painful symptoms. The advanced stage of endometriosis may lead to gynecological malignancies, such as ovarian cancer, and other complications, including infertility. However, its exact physiopathology is not well known. Recent studies have shown the possible roles of inflammation along with oxidative stress. Additionally, angiogenesis and apoptosis dysregulation contribute to endometriosis pathophysiology. Therapeutic strategies and continuing attempts, to conquer endometriosis should be done regarding molecular signaling pathways. Thus, the present review summarizes current studies and focuses on molecular mechanisms.

Role of interleukin-32 in the pathogenesis of endometriosis: in vitro, human and transgenic mouse data

STUDY QUESTION

Does interleukin-32 (IL-32) play a role in the pathogenesis of endometriosis?

SUMMARY ANSWER

IL-32 might be involved in the pathogenesis of endometriosis through increased viability, proliferation and invasion of endometrial cells.

WHAT IS KNOWN ALREADY

Endometriosis is characterized as a chronic inflammatory disease and several proinflammatory cytokines are suggested to be involved in its pathogenesis and pathophysiology. IL-32, recognized as a new proinflammatory cytokine and a strong inducer of other proinflammatory cytokines, has been shown to serve as a key modulator in several chronic inflammatory diseases.

STUDY DESIGN, SIZE, DURATION

This study included comparison of IL-32 levels in the peritoneal fluids between women with and without endometriosis, in-vitro experiments using Ishikawa cells and endometrial stromal cells (ESCs), and experiments on IL-32 transgenic mice and wild-type mice with induced endometriosis.

PARTICIPANTS/MATERIALS, SETTING, METHODS

IL-32 levels in the peritoneal fluids were measured using enzyme-linked immunosorbent assays. Cell viability, expression of proliferating cell nuclear antigen (PCNA), and cellular invasiveness were analyzed following in-vitro treatment of Ishikawa cells and ESCs with recombinant IL-32 alpha (α) and gamma (γ). Ectopic endometriotic lesions were compared between IL-32 transgenic mice and wild-type mice after autologous endometrial transplantation with immunohistochemistry for Ki-67 antigen and PCNA.

MAIN RESULTS AND THE ROLE OF CHANCE

The peritoneal fluid concentration of IL-32 was significantly higher in patients with advanced stage endometriosis compared with the controls. In-vitro treatment with IL-32 α and γ caused significant increases in cellular viability, PCNA expression, and invasiveness in Ishikawa cells and ESCs. The IL-32 transgenic mice had a significantly larger size of the ectopic endometrial lesions with higher expression of Ki-67 antigen and PCNA compared with wild-type mice.

LARGE SCALE DATA

N/A.

LIMITATIONS, REASONS FOR CAUTION

It is still unclear whether IL-32 is a main regulator, or one of several downstream proinflammatory cytokines, causing establishment and/or progression of endometriosis.

WIDER IMPLICATIONS OF THE FINDINGS

Further investigation on IL-32 signaling pathways may contribute to development a more effective treatment of endometriosis.

STUDY FUNDING/COMPETING INTEREST(S)

This research was supported by a grant of the Korea Health Technology R&D Project through the Korea Health Industry Development Institute (KHIDI), funded by the Ministry of Health & Welfare, Republic of Korea (Grant number: HI16C1682). None of the authors has anything to disclose.

Increased α2-6 sialylation of endometrial cells contributes to the development of endometriosis

Endometriosis is a disease characterized by implants of endometrial tissue outside the uterine cavity and is strongly associated with infertility. Focal adhesion of endometrial tissue to the peritoneum is an indication of incipient endometriosis. In this study, we examined the effect of various cytokines that are known to be involved in the pathology of endometriosis on endometrial cell adhesion. Among the investigated cytokines, transforming growth factor-β1 (TGF-β1) increased adhesion of endometrial cells to the mesothelium through induction of α2-6 sialylation. The expression levels of β-galactoside α2-6 sialyltransferase (ST6Gal) 1 and ST6Gal2 were increased through activation of TGF-βRI/SMAD2/3 signaling in endometrial cells. In addition, we discovered that terminal sialic acid glycan epitopes of endometrial cells engage with sialic acid-binding immunoglobulin-like lectin-9 expressed on mesothelial cell surfaces. Interestingly, in an in vivo mouse endometriosis model, inhibition of endogenous sialic acid binding by a NeuAcα2-6Galβ1-4GlcNAc injection diminished TGF-β1-induced formation of endometriosis lesions. Based on these results, we suggest that increased sialylation of endometrial cells by TGF-β1 promotes the attachment of endometrium to the peritoneum, encouraging endometriosis outbreaks.

A growth factor involved in cell differentiation and proliferation contributes to the development of endometriosis by stimulating a protein modification mechanism that increases the adhesiveness of cells lining the uterus. Endometriosis results when these cells, known as endometrial cells, start growing outside the uterus causing pelvic pain, heavy periods and, in some cases, infertility. Ki-Tae Ha at Pusan National University, Yangsan, South Korea, and colleagues found that transforming growth factor-β1 signaling promoted the addition of sialic acid sugar units onto endometrial cell surface proteins. This modification enhanced the adhesion of endometrial cells to mesothelial cells, which line other internal organs, and the formation of endometriosis lesions in mice. Preventing sialic acid binding to its mesothelial cell receptor reduced lesion formation. The findings reveal a new molecular mechanism underlying endometriosis and a potential treatment strategy.

The involvement of multifunctional TGF-β and related cytokines in pathogenesis of endometriosis

PURPOSE

Transforming growth factor β (TGF-β) is one of the major immune and inflammation factors responsible for regulating cell proliferation, differentiation, angiogenesis, and immune responses. Deregulated TGF-β activity, especially its influence in peritoneal cytokine cross-talk, has been implicated in pathologies of endometriosis. The aim of this study was to determine whether TGF-β could be involved in the pathogenesis of endometriosis. For this purpose, we evaluated concentrations of TGFβ1, TGF-β2, TGF-β3 and interleukin (IL)-1β, IL-6, IL-10, IL-17, IL-21 and IL-22 in peritoneal fluid (PF) and serum of women with endometriosis.

METHODS

A total of 66 women of reproductive age were involved in the study, 51 endometriosis patients, and 15 women from the control group. PF and serum levels of all cytokines were measured with ELISA in women with or without endometriosis.

RESULTS

Higher PF and serum levels of TGF-β1, TGF-β2, TGF-β3, presented also as a total TGF-β in women with endometriosis compared to control were observed. The biggest increase was measured in the case of TGF-β1. The higher levels of IL-1β, IL-6, IL-10, and IL-17 in PF and serum of endometriosis women than control was observed. Higher PF levels of studied parameters in comparison with serum levels were found.

CONCLUSIONS

In endometriosis, TGF-β could affect differentiation of T helper (Th) cells, hence produce more IL-17 and IL-10 to PF and might have an indirect influence on inflammation, which is associated with higher IL-1β and IL-6 levels. In consequent, TGF-β in peritoneal fluid may promote an environment favorable to ectopic lesion formation.

Usefulness of hematological parameters for differential diagnosis of endometriomas in adolescents/young adults and older women

BACKGROUND

Inflammatory processes have been considered to be involved in the pathogenesis of endometriosis. However, the predictive role of inflammatory hematological parameters in endometriosis is not clear. The aim of this study was to analyze the clinical value of hematologic markers in the differential diagnosis of endometriomas in younger and older reproductive age women.

MATERIALS AND METHODS

A retrospective chart review was done for 502 patients who underwent surgery: 267 with endometriomas (endometrioma group) and 235 with other benign adnexal cysts (control group). Patients were placed into subgroups as younger (adolescents/young adults, aged <25 years) and older (aged ≥25 years) women. Total and differential white blood cell count, neutrophil-to-lymphocyte ratio, platelet indices and platelet-to-lymphocyte ratio (PLR) were evaluated with receiver operating characteristic curve analysis for differential diagnosis of endometriomas.

RESULTS

The mean serum levels of PLR, plateletcrit (PCT), platelet count and CA-125 (reference range below 35 IU/mL) were significantly higher in the endometrioma group (p < 0.001). The area under the curve (AUC) for CA-125 was 0.85 [95% confidence interval (CI), 0.82-0.88] (p < 0.001) for the entire group. However, platelet count, PLR, and PCT showed poor discriminative ability for detecting endometriomas with AUC values of 0.59 (95% CI, 0.55-0.65, p < 0.001), 0.58 (95% CI, 0.53-0.63, p = 0.002) and 0.61 (95% CI, 0.56-0.66, p < 0.001), respectively. In age-stratified analysis, these platelet indices had also low diagnostic performance in both age groups.

CONCLUSIONS

Hematologic markers do not adequately differentiate ovarian endometriomas from other benign cysts in neither adolescents/young adults nor older women.

Chronic Niche Inflammation in Endometriosis-Associated Infertility: Current Understanding and Future Therapeutic Strategies

Endometriosis is an estrogen-dependent inflammatory disease that affects up to 10% of women of reproductive age and accounts for up to 50% of female infertility cases. It has been highly associated with poorer outcomes of assisted reproductive technology (ART), including decreased oocyte retrieval, lower implantation, and pregnancy rates. A better understanding of the pathogenesis of endometriosis-associated infertility is crucial for improving infertility treatment outcomes. Current theories regarding how endometriosis reduces fertility include anatomical distortion, ovulatory dysfunction, and niche inflammation-associated peritoneal or implantation defects. This review will survey the latest evidence on the role of inflammatory niche in the peritoneal cavity, ovaries, and uterus of endometriosis patients. Nonhormone treatment strategies that target these inflammation processes are also included. Furthermore, mesenchymal stem cell-based therapies are highlighted for potential endometriosis treatment because of their immunomodulatory effects and tropism toward inflamed lesion foci. Potential applications of stem cell therapy in treatment of endometriosis-associated infertility in particular for safety and efficacy are discussed.

Inflammatory cytokine profile of co‑cultivated primary cells from the endometrium of women with and without endometriosis

Endometriosis is a chronic gynecological disorder defined as the presence of endometrial tissue within extra-uterine sites. The primary symptoms are infertility and chronic pain. The inflammatory environment and aberrant immune responses in women with endometriosis may be directly associated with the initiation and progression of endometriotic lesions. In the present study, the secretion of inflammatory cytokines was evaluated in cultures of primary endometrial cells (ECs) isolated from the endometrium of women with and without endometriosis. The presence of endometriotic cells leads to alterations in the secretory profile of healthy ECs. The expression of the inflammatory cytokines interleukin (IL)‑6 and IL‑8 was significantly increased in endometriotic and co‑cultured cells compared with healthy ECs. IL‑6 expression was strongly correlated with IL‑8 expression in endometriotic cells. IL‑1β expression was increased on day 10 of co‑culture to 48.30 pg/ml and may be associated with the long‑term co‑culture, rather than IL‑6 and IL‑8 expression. IL‑6 expression was strongly correlated with cell number, whereas IL‑8 expression was moderately correlated with cell number. Additionally, it was observed that co‑cultured cells exhibited a different population of cells, with expression of the mesenchymal stem cell marker cell surface glycoprotein MUC18, indicating a putative role of endometrial mesenchymal stem cells in the secretion of cytokines and disease development. These results indicate a predominant role of primary endometriotic cells in the secretion of cytokines, which contributes to the disrupted peritoneal and endometrial environment observed in the women with endometriosis.

Effect of interleukin-1β and lipoxin A4 in human endometriotic stromal cells: Proteomic analysis

AIM

Lipoxin A₄ (LXA₄ ) can function as an endogenous 'breaking signal' in inflammation and plays an important role in the progression of endometriosis. The proteome responses to interleukin-1β (IL-1β) or LXA₄ in human endometriotic stromal cells (ESC) are not well understood.

METHODS

In this study, primary ESC were cultured from ovarian endometriosis tissue. Three groups were established: the control group; the IL-1β stimulation group; and the IL-1β and LXA₄ incubation group. Proteins were assessed on 2-D polyacrylamide gel electrophoresis (2D-PAGE), and differentially expressed protein spots were further identified on matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) mass spectrometry (MALDI-TOF-MS). Wound healing and transwell assays were performed to assess the migration and invasion of ESC after treatment.

RESULTS

In total, 40 differentially expressed protein spots were identified successfully on MALDI-TOF-MS. The proteins identified were related to cell structure, metabolism, signal transduction, protein synthesis and membrane structure, processes that may be involved in the development of endometriosis. Vinculin and IL-4 were further analyzed on western blot and quantitative real-time polymerase chain reaction. Moreover, LXA₄ could suppress the migration and invasion of ESC induced by IL-1β.

CONCLUSION

LXA₄ may inhibit the progression of endometriosis partly by lowering or raising the effect of IL-1β, mediated via some inflammation-related proteins (e.g. vinculin) and immune response-related protein (e.g. IL-4) in vitro.

Physical activity and endometriosis risk in women with infertility or pain: Systematic review and meta-analysis

BACKGROUND

The potential association between endometriosis and physical activity (PA) has been suggested in several epidemiological studies.We aimed to establish whether PA influences endometriosis risk.

METHODS

MEDLINE and EMBASE were searched using "physical activity" OR "exercise" combined with "endometriosis," in Medical Subject Headings and free text. We selected original articles in English, published up to April 2016, evaluating the association between endometriosis and recent or past PA (case-control or cohort studies). References of retrieved papers were reviewed. We computed summary odds ratios (ORs) of endometriosis for recent and past PA.

RESULTS

Six case-control and 3 cohort studies included 3355 cases for recent PA and 4600 cases for past PA. The summary OR for endometriosis according to PA level, calculated by the random-effect model, was 0.85 [95% confidence interval (CI) 0.67-1.07] for any recent versus no PA. As compared to no recent PA, ORs for low and moderate/high PA were 1.00 (95% CI: 0.68-1.28) and 0.75 (95% CI: 0.53-1.07), respectively.

CONCLUSIONS

Though it suggests that PA may reduce the risk of endometriosis, this meta-analysis does not conclusively support the hypothesis. Whether our findings are really explained by the benefit of exercise at molecular and endocrine level, or related to confounding mechanisms, such as study design, choice of controls, and PA potentially improving pain, needs to be further investigated.

Endometriosis: where are we and where are we going?

Endometriosis currently affects ~5.5 million reproductive-aged women in the U.S. with symptoms such as painful periods (dysmenorrhea), chronic pelvic pain, pain with intercourse (dyspareunia), and infertility. It is defined as the presence of endometrial tissue outside the uterine cavity and is found predominately attached to sites within the peritoneal cavity. Diagnosis for endometriosis is solely made through surgery as no consistent biomarkers for disease diagnosis exist. There is no cure for endometriosis and treatments only target symptoms and not the underlying mechanism(s) of disease. The nature of individual predisposing factors or inherent defects in the endometrium, immune system, and/or peritoneal cavity of women with endometriosis remains unclear. The literature over the last 5 years (2010-2015) has advanced our critical knowledge related to hormones, hormone receptors, immune dysregulation, hormonal treatments, and the transformation of endometriosis to ovarian cancer. In this review, we cover the aforementioned topics with the goal of providing the reader an overview and related references for further study to highlight the progress made in endometriosis research, while concluding with critical areas of endometriosis research that are urgently needed.

Bentamapimod (JNK Inhibitor AS602801) Induces Regression of Endometriotic Lesions in Animal Models

Endometriosis is an estrogen (ER)-dependent gynecological disease caused by the growth of endometrial tissue at extrauterine sites. Current endocrine therapies address the estrogenic aspect of disease and offer some relief from pain but are associated with significant side effects. Immune dysfunction is also widely believed to be an underlying contributor to the pathogenesis of this disease. This study evaluated an inhibitor of c-Jun N-terminal kinase, bentamapimod (AS602801), which interrupts immune pathways, in 2 rodent endometriosis models. Treatment of nude mice bearing xenografts biopsied from women with endometriosis (BWE) with 30 mg/kg AS602801 caused 29% regression of lesion. Medroxyprogesterone acetate (MPA) or progesterone (PR) alone did not cause regression of BWE lesions, but combining 10 mg/kg AS602801 with MPA caused 38% lesion regression. In human endometrial organ cultures (from healthy women), treatment with AS602801 or MPA reduced matrix metalloproteinase-3 (MMP-3) release into culture medium. In organ cultures established with BWE, PR or MPA failed to inhibit MMP-3 secretion, whereas AS602801 alone or MPA + AS602801 suppressed MMP-3 production. In an autologous rat endometriosis model, AS602801 caused 48% regression of lesions compared to GnRH antagonist Antide (84%). AS602801 reduced inflammatory cytokines in endometriotic lesions, while levels of cytokines in ipsilateral horns were unaffected. Furthermore, AS602801 enhanced natural killer cell activity, without apparent negative effects on uterus. These results indicate that bentamapimod induced regression of endometriotic lesions in endometriosis rodent animal models without suppressing ER action. c-Jun N-terminal kinase inhibition mediated a comprehensive reduction in cytokine secretion and moreover was able to overcome PR resistance.

Anti-Müllerian Hormone in Peritoneal Fluid and Plasma From Women With and Without Endometriosis

Anti-Müllerian hormone (AMH) has potential local effects on ovarian function and endometrial tissue, including endometriosis, but its presence in peritoneal fluid is not fully understood. This is a cross-sectional study evaluating AMH in peritoneal fluid and plasma from women with endometriosis (N = 61) and from control women without endometriosis (N = 36). There was a significant correlation between AMH in plasma and peritoneal fluid from both patients with endometriosis (r(2) = .767 [P < .001]) and control participants (r(2) = .647 [P < .001]) less than 45 years of age. Anti-Müllerian hormone declined with women's increasing age in both plasma and peritoneal fluid in women with and without endometriosis. There were no differences in the plasma or peritoneal fluid AMH in women with endometriosis versus control women. The strong relationship between plasma and peritoneal fluid may allow plasma AMH to be a marker for peritoneal AMH in studies evaluating the local effects of AMH.

Diagnostic potential of peritoneal fluid biomarkers of endometriosis

Endometriosis is defined as the presence of endometrial glands and stroma outside the uterus, in different parts of the peritoneal cavity. It affects up to 10% of reproductive-age women and up to 50% of women with infertility. Surgical diagnosis of endometriosis is still the gold standard, with no diagnostic biomarkers available. Medical therapies target the symptoms and not the disease itself, and surgical treatment cannot prevent recurrence. As peritoneal fluid reflects the altered peritoneal microenvironment of endometriosis patients, it can provide a wealth of information on pathophysiological processes and potential biomarkers. This report reviews the molecular biomarkers identified in peritoneal fluid over the last 5 years and discusses their potential applications for diagnosis, prognosis and drug therapy.

Identification of local angiogenic and inflammatory markers in the menstrual blood of women with endometriosis

The aim of this study was to evaluate the presence of myeloperoxidase (MPO), N-acetyl-β-D-glucosaminidase (NAG), tumor necrosis factor alpha (TNF-α) and vascular endothelial growth factor (VEGF) in peripheral and menstrual blood in women with (n=10) and without (n=7) endometriosis. NAG and MPO activities were evaluated by enzymatic methods, whereas TNF-α and VEGF by immunoassay. No significant differences were found for these markers, neither in menstrual nor in peripheral blood between groups. Menstrual blood NAG (P=0.039) and MPO (P=0.0117) activities in the endometriosis group were significantly higher than in peripheral blood. NAG and MPO presented positive linear correlation in peripheral (P=0.07; r=0.641) and menstrual blood (P=0.01; r=0.603). These findings point to the existence of an increased local inflammatory activity in women with endometriosis.

Interplay between Misplaced Müllerian-Derived Stem Cells and Peritoneal Immune Dysregulation in the Pathogenesis of Endometriosis

In the genetic regulation of Müllerian structures development, a key role is played by Hoxa and Wnt clusters, because they lead the transcription of different genes according to the different phases of the organogenesis, addressing correctly cell-to-cell interactions, allowing, finally, the physiologic morphogenesis. Accumulating evidence is suggesting that dysregulation of Wnt and/or Hox genes may affect cell migration during organogenesis and differentiation of Müllerian structures of the female reproductive tract, with possible dislocation and dissemination of primordial endometrial stem cells in ectopic regions, which have high plasticity to differentiation. We hypothesize that during postpubertal age, under the influence of different stimuli, these misplaced and quiescent ectopic endometrial cells could acquire new phenotype, biological functions, and immunogenicity. So, these kinds of cells may differentiate, specializing in epithelium, glands, and stroma to form a functional ectopic endometrial tissue. This may provoke a breakdown in the peritoneal cavity homeostasis, with the consequent processes of immune alteration, documented by peripheral mononuclear cells recruitment and secretion of inflammatory cytokines in early phases and of angiogenic and fibrogenic cytokines in the late stages of the disease.

Diagnostic accuracy of interleukin-6 levels in peritoneal fluid for detection of endometriosis

PURPOSE

To determine, with extended receiver operating characteristic (ROC) curve analysis, the diagnostic value of cytokines showing significantly different peritoneal concentrations between women with and without endometriosis.

METHODS

Multiplex cytokine concentration measurement of IL-2, IL-4, IL-6, IL-10, TNF-α and IFN-γ levels in peritoneal fluid of women with minimal to mild (n = 10) and moderate to severe (n = 26) endometriosis, and 42 controls.

RESULTS

Only IL-6 and IL-10 concentrations were significantly higher in endometriosis patients than in controls. Specifically, significantly higher IL-6 and IL-10 levels were found in moderate to severe but not in minimal to mild endometriosis as compared to controls. For evaluation of diagnostic significance, ROC analysis determined discriminating parameters for IL-6, while those calculated for IL-10 were useless. Importantly, ROC analysis for IL-6 levels limited to women with moderate to severe endometriosis showed the highest area under the curve with the sample size sufficient to achieve 90 % power of the test. Finally, extended ROC including cost of analysis for this group of patients determined the optimal cut-off leading to high specificity and positive likelihood ratio resulting in 79 % effectiveness of the test.

CONCLUSIONS

While our outcomes show moderate usefulness of peritoneal IL-6 levels in discrimination of moderate to severe endometriosis, further studies might be needed to determine the usefulness of peritoneal IL-6 levels in detection of early stages of endometriosis, as such a finding would be more relevant in clinical decision making.

Dietary fish oil supplementation inhibits formation of endometriosis-associated adhesions in a chimeric mouse model

OBJECTIVE

To examine whether dietary fish oil supplementation reduces development of spontaneous endometriosis-associated adhesions using an established model.

DESIGN

Laboratory-based study.

SETTING

Medical center research laboratory. PATIENT(S)/ANIMAL(S): Disease-free women of reproductive age and nude mice.

INTERVENTION(S)

Women were not provided any intervention. Mice were randomized to receive fish oil supplementation or control diet.

MAIN OUTCOME MEASURE(S)

Experimental endometriosis was established in mice via injection of human endometrial tissue within 16 hours of ovariectomy. Mice were provided standard or menhaden fish oil-supplemented diets for ≥ 2 weeks before initiation of experimental endometriosis and until killing them 1 week later. At necropsy, mice were examined for the presence and extent of adhesions and endometriotic-like lesions. Tissues were excised and morphologically characterized.

RESULT(S)

Adhesions/lesions were reduced in mice provided with dietary fish oil compared with control animals. Leukocytes were more numerous within the adhesions/lesions of the mice maintained on the standard diet compared with animals provided with fish oil. As indicated by staining intensity, collagen deposition was greater at adhesion sites within control mice compared with fish oil-supplemented animals.

CONCLUSION(S)

Wound-healing associated with surgery created an inflammatory peritoneal microenvironment that promoted the development of both experimental endometriosis and adhesions in a murine model. Targeting excessive inflammation with fish oil may be an effective adjuvant therapy to reduce the development of postsurgical adhesions related to endometriosis.