Circulating and peritoneal fluid interleukin-6 levels and gene expression in pelvic endometriosis

MCP-1 exerts the inflammatory response via ILK activation during endometriosis pathogenesis

AIMS

MCP-1 has been shown to be elevated in endometriosis. ILK functions in several cellular events and interacts with MCP-1-signaling. In the current study, we evaluated the role of MCP-1-ILK signaling in human endometriotic cell's (Hs832(C).TCs) potential for colonization, invasion, adhesion, etc. and differentiation of macrophage along with inflammation in an endometriosis mouse model.

MATERIALS AND METHODS

A mouse model of endometriosis with elevated levels of MCP-1 was developed by injecting MCP-1. We examined the migration, adhesion, colonization and invasion of Hs832(C).TCs in response to MCP-1-ILK signaling. We also examined the differentiation of THP-1 cells to macrophage in response to MCP-1-ILK signaling.

KEY FINDINGS

We observed that MCP-1 increased Ser246 phosphorylation of ILK in Hs832(C).TCs and enhanced the migration, adhesion, colonization, and invasion of Hs832(C).TCs. In the mouse model of endometriosis, we found elevated chemokines (CCL-11, CCL-22 and CXCL13) levels. An increased level of MCP-1 mediated ILK activation, leading to increased inflammatory reaction and infiltration of residential and circulatory macrophages, and monocyte differentiation, but suppressed the anti-inflammatory reaction. The inhibitor (CPD22) of ILK reversed the MCP-1-mediated action by restoring Hs832(C).TCs and THP-1 phenotype. ILK inhibition in a mouse model of endometriosis reduced the effects of MCP-1 mediated pro-inflammatory cytokines, but increased anti-inflammatory response along with T-regulatory and T-helper cell restoration.

SIGNIFICANCE

Targeting ILK restores MCP-1 milieu in the peritoneal cavity and endometrial tissues, reduces the inflammatory response, improves the T-regulatory and T-helper cells in the endometriosis mouse model and decreases the migration, adhesion, colonization and invasion of endometriotic cells.

The association between genetically predicted systemic inflammatory regulators and endometriosis: A bidirectional Mendelian randomization study

Elevated levels of various cellular inflammatory markers have been observed in patients with endometriosis (EMs). However, a causal relationship between these markers and EMS has not been firmly established. This study aimed to assess the causality between cellular inflammatory markers and the onset of EMS using a bidirectional Mendelian randomization approach. Genetic associations for EMs were derived from the largest and most recent genome-wide association study (GWAS) involving 1937 EMS cases and 245,603 controls of European ancestry. Single nucleotide polymorphisms associated with 41 cellular cytokines and other systemic inflammatory regulators were identified from 8293 Finnish participants. Estimates were obtained using inverse-variance weighted, with sensitivity analyses conducted using MR-Egger, weighted median, and MR-PRESSO. Among the 41 systemic inflammatory regulators included in the analysis, none were associated with the risk of EMs. Elevated levels of IL-6 were associated with an increased risk of EMs (OR = 1.351, 95%CI = 1.015-1.797). Conversely, genetically predicted elevated levels of platelet-derived growth factor (PDGF-BB) were associated with a reduced risk of EMs (OR = 0.856, 95%CI = 0.742-0.987). Genetically predicted elevations in IL-6 may contribute to an increased risk of EMs, while elevated PDGF-BB levels appear protective, suggesting potential therapeutic targets for EMs. Other systemic inflammatory regulators seem unrelated to EMs risk, potentially representing downstream effects or consequences of shared factors between inflammation and EMs.

Cytokine and chemokine profiles in women with endometriosis, polycystic ovary syndrome, and unexplained infertility

Numerous factors (including immunological, congenital, hormonal, and morphological disorders) can lead to infertility. In this regard, 3 specific diseases associated with infertility are discussed in this review study (i.e., polycystic ovary syndrome [PCOS], endometriosis [EMS], and unexplained infertility [UI]). PCOS is a common endocrine disorder characterized by chronic low-grade inflammation, and EMS is a benign disease characterized by the presence of ectopic endometrial tissue. UI refers to couples who are unable to conceive for no known reason. Conception and pregnancy are significantly affected by the immune system; in this regard, chemokines and cytokines play important roles in the regulation of immune responses. Patients with PCOS, EMS, and UI have altered cytokine and chemokine profiles, suggesting that dysregulation of these molecules may contribute to infertility in these conditions. Accordingly, the issue of infertility is addressed in this review study, a condition that affects approximately 16% of couples worldwide.

Diagnostic accuracy of interleukin-6 in multiple diseases: An umbrella review of meta-analyses

Objective

This review aims to conduct a comprehensive study of the diagnostic accuracy of interleukin-6 (IL-6) for multiple diseases by utilizing existing systematic reviews and meta-analyses.

Methods

We performed a thorough search of Embase, Web of Science, PubMed, and Cochrane Database of Systematic Reviews up to April 2023 to gather meta-analyses that investigate the diagnostic accuracy of IL-6. To assess the methodological quality of the studies, we employed the Assessing the Methodological Quality of Systematic Reviews-2 and Grading of Recommendations, Assessment, Development and Evaluation criteria.

Results

We included 34 meta-analyses out of the 3024 articles retrieved from the search. These meta-analyses covered 9 categories of diseases of the International Classification of Diseases-11. Studies rated as "Critically Low" or "Very Low" in the quality assessment process were excluded, resulting in a total of 6 meta-analyses that encompassed sepsis, colorectal cancer, tuberculous pleural effusion (TPE), endometriosis, among others. Among these diseases, IL-6 demonstrated a relatively high diagnostic potential in accurately identifying TPE and endometriosis.

Conclusions

IL-6 exhibited favorable diagnostic accuracy across multiple diseases, suggesting its potential as a reliable diagnostic biomarker in the near future. Substantial evidence supported its high diagnostic accuracy, particularly in the cases of TPE and 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.

Neurotrophins and Their Receptors, Novel Therapeutic Targets for Pelvic Pain in Endometriosis, Are Coordinately Regulated by IL-1β via the JNK Signaling Pathway

Pelvic pain in women with endometriosis is attributed to neuroinflammation and afferent nociceptor nerves in ectopic and eutopic endometrium. The hypothesis that uterine nociception is activated by IL-1β, a prominent cytokine in endometriosis, was tested herein. Immunofluorescence histochemistry confirmed the presence of neurons in human endometrial tissue. Expression of nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF) and their receptors in endometrial tissue and cells was validated by immunohistochemistry and Western blotting. Isolated endometrial stromal cells (ESCs) were subjected to dose-response and time-course experiments with IL-1β and kinase inhibitors to characterize in vitro biomarkers. Neural biomarkers were co-localized in endometrial nerve fibers. NGF, BDNF, and their receptors tropomyosin receptor kinase (Trk) A, TrkB, and p75 neurotrophin receptor were all expressed in primary ESCs. IL-1β stimulated higher TrkA/B expression in ESCs derived from endometriosis cases (2.8- ± 0.2-fold) than cells from controls (1.5- ± 0.3-fold, t-test, P < 0.01), effects that were mediated via the c-Jun N-terminal kinase (JNK) pathway. BDNF concentrations trended higher in peritoneal fluid of endometriosis cases but were not statistically different from controls (P = 0.16). The results support the hypothesis that NGF and BDNF and their corresponding receptors orchestrate innervation of the endometrium, which is augmented by IL-1β. We postulate that JNK inhibitors, such as SP600125, have the potential to reduce neuroinflammation in women with endometriosis.

Possible Correlation between Urocortin 1 (Ucn1) and Immune Parameters in Patients with Endometriosis

The etiology of endometriosis (EMS) has not been clearly elucidated yet, and that is probably the reason why its diagnostic process is frequently long-lasting and inefficient. Nowadays, the non-invasive diagnostic methods of EMS are still being sought. Our study aimed to assess the serum and peritoneal fluid levels of urocortin 1 (Ucn1) in patients with EMS and healthy women. Moreover, considering the immune background of the disease, the association between Ucn1 and several immune parameters was studied in both groups. We found that the serum Ucn1 level was significantly upregulated in women with EMS compared to healthy patients. Moreover, higher serum Ucn1 levels tended to correspond with more advanced stages of the disease (p = 0.031). Receiver operating characteristic (ROC) analysis revealed that based on serum Ucn1 levels, it is possible to distinguish deep infiltrating endometriosis (DIE) from among other EMS types. Together, these results indicate Ucn1 as a possible promising biomarker of EMS: however, not in isolation, but rather to enhance the effectiveness of other diagnostic methods.

Promotion of BST2 expression by the transcription factor IRF6 affects the progression of endometriosis

Background

Endometriosis (EM) is a benign, multifactorial, immune-mediated inflammatory disease that is characterized by persistent activation of the NF-κB signaling pathway and some features of malignancies, such as proliferation and lymphangiogenesis. To date, the pathogenesis of EM is still unclear. In this study, we investigated whether BST2 plays a role in the development of EM.

Methods

Bioinformatic analysis was performed with data from public databases to identify potential candidate targets for drug treatment. Experiments were conducted at the cell, tissue, and mouse EM model levels to characterize the aberrant expression patterns, molecular mechanisms, biological behaviors of endometriosis as well as treatment outcomes.

Results

BST2 was significantly upregulated in ectopic endometrial tissues and cells compared with control samples. Functional studies indicated that BST2 promoted proliferation, migration, and lymphangiogenesis and inhibited apoptosis in vitro and in vivo. The transcription factor (TF) IRF6 induced high BST2 expression by directly binding the BST2 promoter. The underlying mechanism by which BST2 functions in EM was closely related to the canonical NF-κB signaling pathway. New lymphatic vessels may serve as a channel for the infiltration of immune cells into the endometriotic microenvironment; these immune cells further produce the proinflammatory cytokine IL-1β, which in turn further activates the NF-κB pathway to promote lymphangiogenesis in endometriosis.

Conclusion

Taken together, our findings provide novel insight into the mechanism by which BST2 participates in a feedback loop with the NF-κB signaling pathway and reveal a novel biomarker and potential therapeutic target for endometriosis.

TSH receptor antibodies (TRAb) - A potential new biomarker for endometriosis

OBJECTIVES

The prevalence of several autoimmune diseases, including thyroid dysfunction, has been reported to be increased in patients with endometriosis. Upregulated thyroid stimulation hormone (TSH) receptors in ectopic endometrium and elevated serum titers of TSH receptor antibodies (TRAb) IgG in endometriosis patients indicates an overlap in pathophysiology. However, cross-reactivity with other antibodies must be excluded. The objective of this study was to compare the expression of autoantibodies in women with endometriosis and two control groups to evaluate the potential of TRAb IgG as a diagnostic marker for endometriosis.

STUDY DESIGN

This cross-sectional study was carried out in 172 women with surgically confirmed endometriosis and two control groups consisting of 50 healthy blood donors and 114 women from Malmö Offspring Study consisting of people from the general population. Serum levels of thyroid hormones, TSH and TRAb autoantibodies, AXIN1, and autoantibodies against follicle stimulating hormone (FSH), human chorionic gonadotropin (hCG), luteinizing hormone (LH), and their receptors, were analyzed. The patients answered a questionnaire and estimated their gastrointestinal symptoms using the Visual Analogue Scale for Irritable Bowel Syndrome.

RESULTS

Of the endometriosis patients, 29.1 % had TRAb IgG above the present detection limit of ≥ 1.0 IE/L compared to 2.6 % of the controls from MOS (p < 0.001) and 94.5 % had levels of TRAb over the previous detection limit ≥ 0.3 IE/L compared to 7.9 % of the controls (p < 0.001). Titers of both TRAb IgG and IgM were increased in patients compared to controls from MOS and blood donors, respectively (p < 0.001). There was no increase of autoantibodies against FSH, FSH receptor (FSHR), hCG, LH, LH receptor (LHR) or TSH compared to the blood donor controls. TRAb titers did not correlate with age, disease duration, AXIN1, TSH, thyroid hormones or gastrointestinal symptoms.

CONCLUSION

TRAb IgG and IgM are slightly elevated in patients with endometriosis with no cross-reactivity with other autoantibodies. The results indicate that TRAb is truly elevated and thereby has the potential to be used to support the diagnosing of endometriosis.

Construction of Competing Endogenous RNA Networks Incorporating Transcription Factors to Reveal Differences in Granulosa Cells from Patients with Endometriosis

Purpose: This study aimed to reveal the molecular differences in granulosa cells (GCs) from patients with endometriosis (EM). Methods: RNA sequencing was performed on GCs from patients with EM-related infertility (n = 3) and controls (n = 3). Differentially expressed long noncoding RNAs [differentially expressed lncRNAs (DELs), |log2 FC|>4, false discovery rate (FDR) <0.05] and genes [differentially expressed genes (DEGs), |log2 FC|>1.4, FDR <0.05] in patients with EM-related infertility and controls were screened. Protein-protein interaction (PPI) networks of the DEGs were constructed. Then, mRNA-miRNA-lncRNA pairs based on DEGs and DELs were constructed by comprehensive bioinformatics analyses. In addition, overlapping genes identified from both the PPI and mRNA-miRNA-lncRNA pairs were selected. Finally, a competing endogenous RNA (ceRNA) network incorporating transcription factors (TFs) was constructed. Results: A total of 25,806 lncRNAs and 19,684 mRNAs were detected, and 7 DELs and 46 DEGs were identified. Five hub genes from the PPI network were also identified. A single overlapping gene, NR4A2, from both the PPI network and mRNA-miRNA-lncRNA pairs was identified. Finally, a ceRNA network incorporating TFs, including one mRNA (NR4A2), one miRNA (hsa-miR-217), three lncRNAs (XIST, MCM3AP-AS1, and C17orf51), and five TFs (SRF, POLR2A, NRF1, MNT, and TCF7L2), was successfully constructed. Conclusions: The proposed ceRNA network and the prediction of TFs in GCs from EM-related infertility revealed differences in GCs from patients with EM. Importantly, the novel TFs, lncRNAs, miRNAs, and mRNAs involved in the ceRNA network might provide new insights into the underlying molecular mechanisms of EM-related infertility.

A deep insight into pelvic pain and endometriosis: a review of the literature from pathophysiology to clinical expressions

Endometriosis is a chronic inflammatory disease that affects approximately 10% of women of reproductive age. Its clinical manifestations are highly heterogeneous, but pelvic pain is the most frequent, causing functional disability. Cyclic or acyclic chronic pelvic pain (CPP), dysmenorrhea and dyspareunia are frequent symptoms which often compromise all aspects of the women's quality of life (QoL). The pathophysiology of endometriosis-related pain is extremely complex and not always clear. The aim of this literature review is to focus on recent updates on the clinical presentation, the pathophysiology and the most important mechanisms involved in the pathogenesis of pelvic pain in endometriosis. A literature search in the Cochrane library, PubMed, Scopus and web of Science databases has been performed, identifying articles from January 1995 to November 2020. Several processes seem to be involved in the pathogenesis of pain, but many aspects are still unclear. Scientific evidence has shown that a correlation between pain severity and stage of endometriosis rarely occurs, whereas there is a significant correlation between pain and the presence of deep endometriosis. Onset and intensity of pain may be due to a complex process involving central sensitization and peripheral activation of nociceptive pathways as well as dysfunction of the immune system and of the hypothalamic-pituitary-adrenal (HPA) axis. A deeper understanding of these different pathogenetic mechanisms may improve future treatments in women with painful endometriosis.

Inflammatory Mediators and Pain in Endometriosis: A Systematic Review

BACKGROUND

pain is one of the main symptoms of endometriosis and it has a deleterious effect on a patients' personal and social life. To date, the clinical management of pain includes prolonged medication use and, in some cases, surgery, both of which are disruptive events for patients. Hence, there is an urgency for the development of a sufficient non-invasive medical treatment. Inflammation is one of the causative factors of pain in endometriosis. It is well established that inflammatory mediators promote angiogenesis and interact with the sensory neurons inducing the pain signal; the threshold of pain varies and it depends on the state and location of the disease. The inhibition of inflammatory mediators' synthesis might offer a novel and effective treatment of the pain that is caused by inflammation in endometriosis.

OBJECTIVES

patients with endometriosis experience chronic pelvic pain, which is moderate to severe in terms of intensity. The objective of this systematic review is to highlight the inflammatory mediators that contribute to the induction of pain in endometriosis and present their biological mechanism of action. In addition, the authors aim to identify new targets for the development of novel treatments for chronic pelvic pain in patients with endometriosis.

DATA SOURCES

three databases (PubMed, Scopus, and Europe PMC) were searched in order to retrieve articles with the keywords 'inflammation, pain, and endometriosis' between the review period of 1 January 2016 to 31 December 2020. This review has been registered with PROSPERO (registry number: CRD42020171018). Eligibility Criteria: only original articles that presented the regulation of inflammatory mediators and related biological molecules in endometriosis and their contribution in the stimulation of pain signal were included.

DATA EXTRACTION

two authors independently extracted data from articles, using predefined criteria.

RESULTS

the database search yielded 1871 articles, which were narrowed down to 56 relevant articles of interest according to the eligibility criteria.

CONCLUSIONS

inflammatory factors that promote angiogenesis and neuroangiogenesis are promising targets for the treatment of inflammatory pain in endometriosis. Specifically, CXC chemokine family, chemokine fractalkine, and PGE2 have an active role in the induction of pain. Additionally, IL-1β appears to be the primary interleukin (IL), which stimulates the majority of the inflammatory factors that contribute to neuroangiogenesis along with IL-6. Finally, the role of Ninj1 and BDNF proteins needs further investigation.

Resveratrol treatment reduces expression of MCP-1, IL-6, IL-8 and RANTES in endometriotic stromal cells

Endometriosis is an inflammatory disease affecting reproductive‐aged women. Immunologic disturbance, as well as inflammation, have crucial roles in the pathogenesis of endometriosis. In this study, we evaluated the effects of resveratrol treatment on expression of monocyte chemotactic protein‐1 (MCP‐1), interleukin‐6 (IL‐6), IL‐8, and regulated upon activation, normal T cell expressed and secreted (RANTES) in endometrial stromal cells from patients with endometriosis compared with non‐endometriotic controls. Thirteen eutopic (EuESCs) and nine ectopic (EESCs) endometrial stromal cells from endometriotic patients as well as eleven endometrial stromal cells from non‐endometriotic controls (CESCs) were treated with resveratrol (100 μmol/L) or ethanol, and gene and/or protein expression of MCP‐1, IL‐6, IL‐8 and RANTES was examined at 6, 24 and 48 hours following treatment in the cells from all origins. Resveratrol treatment significantly reduced gene and protein expression of MCP‐1, IL‐6, and IL‐8 in EuESCs and EESCs compared with CESCs (P < .05‐.001, P < .05‐.001 and P < .05‐<.01, respectively), and this reduction was more noticeable in EESCs than EuESCs (P < .05‐<.001). Besides, resveratrol treatment significantly reduced RANTES protein expression in EESCs in all time intervals (P < .05). Resveratrol treatment significantly reduced the expression of MCP‐1, IL‐6, IL‐8 and RANTES in EESCs.

Integrated analysis of mRNA and protein expression profiling in tubal endometriosis

Tubal endometriosis (tubal EM) is a subtype of endometriosis (EM) associated with fallopian tube impairments and infertility. Since the molecular mechanism underlying tubal EM is not clear, we assume that an aberrant transcriptome of fallopian tube epithelium and microenvironment changes caused by cytokines in tubal fluid are possible causes. The aim of this study was to identify potential hub mRNAs/proteins of tubal EM through integrated transcriptomic and proteomic analyses and to elucidate significant pathways, cellular functions, and interaction networks during the initiation and progression of tubal EM. We obtained human fallopian tube epithelium and tubal fluid samples from patients with and without tubal EM. Tubal epithelia were analyzed using microarray, and tubal fluid was analyzed using quantitative label-free LC-MS/MS. We identified differentially expressed genes (DEGs) and differentially expressed proteins (DEPs) and determined common mRNAs/protein. We observed 35 commonly deregulated mRNAs/proteins, and IPA indicated that cellular movement, inflammatory response, and immune cell trafficking were significantly activated during the pathogenesis of tubal EM. We also identified acute phase response signaling pathway activation as a unique pathogenesis signature of tubal EM. Our results demonstrate that an integrated analysis of the transcriptome and proteome has the potential to reveal novel disease mechanisms at a molecular level.

Identification of Serum Biomarkers for Diagnosis of Endometriosis Using Multiplex Immunoassays

Endometriosis is a common gynecologic disorder characterized by chronic pelvic pain, dysmenorrhea, and infertility. Although this condition places significant financial burden on the healthcare system and negatively affects patient's quality of life, the pathophysiology of the disease remains unclear, and noninvasive diagnostic methods are insufficient. The object of this study was to identify potential biomarkers for endometriosis from peripheral blood. We hypothesized that serum biomarkers modified in endometriosis patients would be detected by multiplex cytokine panel, and identification of a combination of these biomarkers would improve diagnostic power. A total of 141 women, aged 15-52 years with regular menstruation, participated in this study. Twenty-one serum cytokines were detected using the commercially available MILLIPLEX MAP Human Cytokine/Chemokine Kit Panel IV. Among these cytokines, breast- and kidney-expressed chemokine (BRAK)/chemokine (C-X-C motif) ligand 14 (CXCL14) was significantly decreased, and proliferation-inducing ligand (APRIL)/tumor necrosis factor ligand superfamily member 13 (TNFSF13) was significantly increased in endometriosis group. APRIL/TNFSF13 and BRAK/CXCL14 alone or in combination, however, failed to show adequate sensitivity or specificity for the diagnosis of endometriosis. Combination of APRIL/TNFSF13 and BRAK/CXCL14 with serum CA-125 levels yielded significantly higher sensitivity (71.2%) for detecting endometriosis without compromising specificity (80.8%) than CA-125 alone in a logistic regression model (P = 0.050). In conclusion, we identified a biomarker combination that detects endometriosis better than CA125 alone. Therefore, we conclude that multiplex cytokine panel is an efficient method for detecting endometriosis, and analysis of additional cytokine panels may lead to identification of a novel biomarker combination with superior diagnostic power.

Endometrioma, the follicular fluid inflammatory network and its association with oocyte and embryo characteristics

RESEARCH QUESTION

What is the association between endometrioma-affected ovaries, their follicular fluid inflammatory microenvironment, and ovary-specific oocyte and embryo yield and quality?

DESIGN

Exposure-matched prospective cohort study conducted at a university-affiliated infertility clinic. Thirty-four women presenting for oocyte retrieval were enrolled between 2012 and 2013: women with unilateral endometrioma and no other observed peritoneal or deep lesions (n = 10) and women with no signs or symptoms of endometriosis (n = 24). Follicular fluid was aspirated at the time of oocyte retrieval. Samples from each ovary were analysed using a 27-plex immunoassay panel. The associations were evaluated by ovary-specific endometrioma exposure status (affected, unaffected, unexposed) with cytokine levels, oocyte yield and embryo quality.

RESULTS

Levels of interleukin (IL)-8 and monocyte chemoattractant protein-1 were higher in fluid obtained from endometrioma-affected ovaries compared with the unexposed ovaries from women without endometriosis, with intermediate levels observed in the contralateral unaffected ovaries. More modest differences were observed for IL-1β and IL-6. The affected ovaries of women with endometriosis yielded fewer oocytes (mean ± SD = 4.6 ± 2.3) compared with both the unaffected (6.0 ± 3.8) and unexposed (7.9 ± 5.6) ovaries. After adjusting for potential confounders and variables generated in a cytokine principal components analysis, oocyte yield remained slightly lower for the endometrioma-affected ovaries compared with unexposed ovaries. No informative differences among ovary groups for embryo quality parameters were observed.

CONCLUSIONS

The results suggest that the inflammatory milieu of ovarian endometriosis is strongly localized and has a more modestly systemic effect. The effect of endometriomas on infertility, however, cannot be entirely explained by increased inflammation.

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.

Noninvasive diagnosis of endometriosis: Review of current peripheral blood and endometrial biomarkers

A noninvasive biomarker-based test could help shorten the diagnostic delay for endometriosis. The most investigated biomarker sources are peripheral blood and endometrium. Discovery of endometriosis biomarkers is often hypothesis-driven, i.e. when one or a few biomarkers are investigated based on their role in the disease pathogenesis. Alternatively, a hypothesis-generating approach has been followed using the "omics" technologies. A variety of biomarkers for endometriosis have been investigated, but no biomarker has been validated for clinical use. Many challenges lie ahead in the endometriosis biomarker field. In the future, harmonized collection and reporting methods should allow large-scale international collaboration for highly powered studies.