Association of endocannabinoids with pain in endometriosis.

ABSTRACT: Endocannabinoid (eCB) levels fluctuate in inflammatory conditions and as such may take part in endometriosis-associated pain or even in endometriosis pathogenesis. In this case-control (23 cases and 19 controls) study, targeted lipids were measured in the serum and peritoneal fluid collected during laparoscopy. Endometriosis was confirmed histologically. Dysmenorrhea, abdominal pain, and dyspareunia were assessed using the Numeric Rating Scale for pain. Steroids, eCBs, and related lipids were quantified by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Tumor necrosis factor alpha, IL-8, PAPP-A, PP14, RANTES, OPG, MIDKINE, MCP-1, VEGF, leptin, and defensins were quantified by ELISA. We found that eCB levels were significantly influenced by both noncyclic and cyclic abdominal pain. Specifically, women suffering from noncyclic abdominal pain were characterized by a higher 2-AG level in the peritoneal fluid throughout the menstrual cycle, whereas women suffering from dysmenorrhea had higher 2-AG levels and lower AEA levels during the proliferative phase alone. In addition, 2-AG positively correlated with prostaglandin E2 (PGE2), and the ratio AEA/2-AG positively correlated with defensins, suggesting a possible link between endocannabinoids system and inflammatory pain. The results of the current study indicate that the eCB system may play a role in endometriosis-associated pain, but additional studies are needed to investigate the causal relationship.

Gonadotrophin stimulation reduces follicular fluid hormone concentrations and disrupts their quantitative association with cumulus cell mRNA.

RESEARCH QUESTION: Do follicular fluid hormone concentrations and the mRNA expression of LHCG, FSH and androgen receptors, aromatase and anti-Müllerian hormone (AMH) in cumulus granulosa cells differ in naturally matured and stimulated follicles? DESIGN: Cross-sectional study involving 57 natural cycle IVF (NC-IVF) and 36 conventional gonadotrophin-stimulated IVF (cIVF) cycles performed between 2014 and 2016. cIVF was performed by ovarian stimulation with human menopausal gonadotrophin and gonadotrophin-releasing hormone antagonists. Hormone concentrations were determined in the follicular fluid of the leading follicle, and mRNA concentrations were quantified by reverse transcription polymerase chain reaction in RNA extracted from granulosa cells of the cumulus oophorus complex obtained from these fluids. RESULTS: Follicular fluid hormone concentrations were significantly lower in cIVF compared with NC-IVF follicles. Median concentrations were 0.50 and 14.5 mIU/ml for LH (P < 0.001), 16.1 and 46.5 nmol/l for testosterone (P < 0.001), 1270 and 2675 nmol/l for oestradiol (P < 0.001), and 12.3 and 28.9 pmol/l for AMH (P < 0.001), respectively. In cumulus granulosa cells, mRNA concentrations for LH receptor, FSH receptor, androgen receptor, aromatase and AMH did not differ between cIVF and NC-IVF follicles. Several hormone and mRNA concentrations were quantitatively associated in natural cycles such as follicular fluid AMH and cumulus granulosa cells AMH RNA (r2 = 0.107, P = 0.013), follicular fluid testosterone and cumulus granulosa cell AMH RNA (r2 = 0.158, P = 0.002), follicular fluid oestradiol and cumulus granulosa cell AMH RNA (r2 = 0.105, P = 0.014) and follicular fluid oestradiol and aromatase (r2 = 0.113, P = 0.011). In contrast, these associations were not observed in stimulated cycles. CONCLUSION: These findings indicate some effects of gonadotrophin stimulation on follicular physiology, which could be a cause for the previously suggested lower oocyte quality in cIVF compared with NC-IVF.

The endocrine milieu in naturally matured follicles is different in women with high serum anti-Müllerian hormone concentrations.

RESEARCH QUESTION: Is the endocrine milieu different in women with low serum anti-Müllerian hormone (AMH) concentration compared with women with high concentration? DESIGN: Cohort study of 84 women (four groups) classified according to AMH concentration and age undergoing natural cycle IVF treatment. Concentrations of LH, oestradiol, testosterone, androstenedione and AMH were determined in follicular fluid (FF), associations analysed and clinical outcome parameters evaluated. RESULTS: A positive correlation between serum and FF AMH concentrations was confirmed. Follicular fluid androstenedione concentration was positively correlated with serum AMH concentration (P < 0.0001, r2 = 0.197). The correlation between FF LH and FF testosterone concentration in all women was not significant (P = 0.050, r2 = 0.046); however, the correlation between FF androstenedione in women with high serum AMH concentration was significant (P = 0.032, r2 = 0.220). Follicular fluid testosterone and androstenedione were positively correlated with FF oestradiol overall and in some individual groups. The high serum AMH concentration group showed the highest FF AMH and androstenedione concentrations and lowest oestradiol-testosterone and oestradiol-androstenedione ratios. High FF AMH concentration was associated with a higher clinical pregnancy rate and high FF oestradiol concentration with a slightly better embryo quality. CONCLUSIONS: Differences in the endocrine milieu in women with high serum AMH concentration seem to be caused by increased follicular LH concentration. In women with high serum AMH concentration, FF androstenedione is increased and ratios of oestradiol-testosterone and oestradiol-androstenedione are decreased, suggesting a disturbed endocrine milieu caused by reduced metabolization of FF androgens into oestrogens. In natural cycles, FF AMH concentrations are positively associated with higher clinical pregnancy rates and oestradiol concentrations with a higher embryo score.

Gonadotropin Stimulation Has Only a Limited Effect on the Concentration of Follicular Fluid Signalling Proteins: An Antibody Array Analysis.

OBJECTIVE: The follicular fluid (FF) plays an essential role in the physiology of the follicle and the oocyte. Gonadotropin stimulation affects the FF steroid hormone and anti-Mullerian hormone (AMH) concentrations, which has been suggested to be the reason for lower oocyte competence in conventional gonadotropin stimulated in vitro fertilisation (cIVF) compared to natural cycle IVF (NC-IVF). To analyse the effect of gonadotropin stimulation on a broad spectrum of signalling proteins, we ran proteomic antibody arrays on FF of women undergoing both treatments NC-IVF and cIVF. METHOD: Twenty women underwent one NC-IVF and one cIVF treatment cycle. Follicular fluids of the first aspirated follicle were compared between the two groups using a protein microarray which included antibodies against 224 proteins related to cell signalling and reference proteins. Each of the 40 albumin-stripped, matched-pair samples was labelled in the reverse-dye (Cy3/Cy5) procedure before undergoing array hybridisation. Signal analysis was performed using normalisation algorithms in dedicated software. Five proteins yielding a value of P < 0.05 in the array experiment (Cystatin A, Caspase-3, GAD65/67, ERK-1, and ERK-2) were then submitted to quantitative determination by ELISA in the same follicular fluids. RESULTS: Array analysis yielded only a small number of differentially expressed signalling markers by unadjusted P values. Adjustment as a consequence of multiple determinations resulted in the absence of any significant differential marker expression on the array. Five unadjusted differentially expressed proteins were quantified immunometrically with antibodies from different sources. Follicular fluid concentrations of Cystatin A and MAP kinase ERK-1 concentrations were significantly higher in the cIVF than in the NC-IVF follicles, while GAD-2 (GAD65/67) did not differ. The assays for Caspase-3 and MAP kinase ERK-2 did not have the required sensitivities. CONCLUSION: In contrast to FF steroid hormones and AMH, FF concentrations of signalling proteins are not or only marginally altered by gonadotropin stimulation.

Ultra-high sensitive C-reactive protein during normal pregnancy and in preeclampsia: a pilot study.

INTRODUCTION: Angiogenic and inflammatory factors have been shown to play an important role in the pathogenesis of preeclampsia. However, there is little information on their interaction. The aims of this study were to investigate the longitudinal pattern of inflammatory markers, such as interleukin-6 (IL-6) and C-reactive protein (CRP) using a novel ultra-high sensitive assay method (uhsCRP), and to explore their relationship with angiogenic factors such as placental growth factor (PLGF), soluble fms-like tyrosine kinase-1 (sFlt-1), and vascular endothelial growth factor (VEGF) in normal pregnancies and pregnancies complicated by preeclampsia. MATERIALS AND METHODS: Serum levels of uhsCRP, IL-6, PLGF, VEGF and s-Flt-1 were longitudinally determined in 16 women with normal, singleton healthy pregnancies at 7-13, 17-22, 27-31 and 37-41 weeks of gestation by ELISA. uhsCRP was measured using a ultra-high sensitivity ELISA test. Serum of women with preeclampsia (n = 15) was available only once, usually in the third trimester of pregnancy. Women with premature rupture of membranes (PROM) or infection such as chorioamnionitis were excluded. Spearman rank correlation, logistic regression, ROC analysis, ANOVA and Mann-Whitney U-test were used for statistical purposes. RESULTS: In normal pregnancies, serum uhsCRP showed a gestational age-dependent increase (r = 0.40; P < 0.001). In women suffering from preeclampsia, uhsCRP levels were higher than in gestational age-matched controls (18010 ±â€Š4763 versus 3026 ±â€Š587 ng/ml; P < 0.001). Similarly, serum IL-6 levels increased throughout pregnancy and correlated with uhsCRP in normal pregnancies and in preeclampsia (n = 64, r = 0.37; P < 0.01 and n = 15, r = 1.00, P < 0.0001). uhsCRP levels were positively correlated with sFlt-1 levels (n = 64, r = 0.34; P < 0.01). CONCLUSION: The increases in uhsCRP (and IL-6) serum levels with advancing gestation indicate a shift towards an inflammatory state during normal pregnancy. The excessive rise in uhsCRP and sFlt-1 in preeclampsia indicate that both may be involved in its pathogenesis. uhsCRP may be useful as an early marker for preeclampsia and studies defining the pattern of its rise throughout pregnancies at risk are urgently needed.

Serum and follicular fluid testosterone concentrations do not correlate, questioning the impact of androgen supplementation on the follicular endocrine milieu.

Basic research into a possible link between serum and follicular fluid androgen concentrations to detemine whether androgen supplementation in low responders affects follicular endocrine milieu is still lacking. Ninety-seven women (aged 28-43 years) undergoing one natural IVF cycle without any hormone stimulation were analysed. Serum and follicular fluid were collected at the time of follicle aspiration, and the concentrations of LH, total testosterone, oestradiol, dehydroepiandrosterone and anti-Mullerian hormone (AMH) were determined. Serum LH (P = 0.003) and AMH (P = 0.026) concentrations, and follicular fluid AMH (P = 0.015) decreased with increasing age. Within follicular fluid, total testosterone was correlated with oestradiol (P < 0.001) and AMH (P = 0.010); LH correlated with AMH (P = 0.005). Correlation analysis of serum and follicular fluid hormone concentrations revealed that LH, oestradiol and AMH correlated (P < 0.001), whereas testosterone did not. Testosterone serum concentrations did not correlate with other follicular fluid hormones, such as dehydroepiandrosterone, oestradiol and AMH, whereas serum LH correlated with follicular flulid AMH (P < 0.008). Follicular fluid hormone concentrations seem to be independent from serum testosterone. Therefore, it is questionable whether an increase in serum testosterone concentration by androgen supplementation could improve the follicular endocrine milieu.

The association between progestins, nuclear receptors expression and inflammation in endometrial stromal cells from women with endometriosis.

Endometriosis is an inflammatory disease and nuclear receptors play a crucial role in mediating the inflammatory response. In endometrial stromal cells (ESC), nuclear receptors expression can be influenced by the local environment. Progestins are first-line, on-label treatments of endometriosis that may have direct effects on endometriotic lesions through these nuclear receptors. Therefore, we investigated whether there was an association between nuclear receptors expression and the influence of progestins on inflammatory cytokines production in a preliminary, in vitro study with primary cultures. ESC from endometrial biopsies of six subjects with histologically confirmed endometriosis were treated for 6 h with medium alone or with TNF-α (10 or 100 ng/ml) in the presence of dienogest (DNG), medroxyprogesterone acetate (MPA) and norethisterone acetate (NETA) 10-5 M. The progestin-mediated change in IL6, IL8 and MCP-1 mRNA transcription was measured, as was the PRA, PRB, GR, AR and MCR protein expression. The change (medium versus TNF-α 10 ng/ml and medium versus TNF-α 100 ng/ml) in IL6 mRNA transcription was positively associated with the change in PRB, but not PRA with both DNG and NETA treatment. The change in IL8 mRNA was negatively associated with AR expression in the presence of NETA. The change in MCP-1 mRNA expression was positively associated with GR expression and negatively associated with MCR after MPA treatment. The associations between the change in cytokines mRNA expression and nuclear receptors protein expression in response to progestins activity may indirectly suggest different activities of these compounds at a local level worthy of further investigations.

TNFα-induced IKKß complex activation influences epithelial, but not stromal cell survival in endometriosis.

STUDY QUESTION: Can the activity of the IκB kinase (IKKß) complex in endometriotic cells contribute to endometriotic lesion survival? SUMMARY ANSWER: There is a constitutive activity of the IKKß catalytic complex in peritoneal and deeply infiltrating lesions that can influence epithelial, but not stromal cell viability. WHAT IS KNOWN ALREADY: Endometriotic lesions exist in an inflammatory microenvironment with higher local concentrations of cytokines, such as tumour necrosis factor α (TNFα). TNFα stimulates the activation of the IKKß complex, an important nodal point in multiple signalling pathways that influence gene transcription, proliferation and apoptosis. However, few data on the regulation of IKKß in endometriotic tissue are currently available. STUDY DESIGN, SIZE, DURATION: A retrospective analysis of endometriotic tissue from peritoneal, ovarian and deeply infiltrating lesions from 37 women. PARTICIPANTS/MATERIALS, SETTING, METHODS: Basal and activated (phosphorylated) IKKß concentrations were analysed by western blotting and immunohistochemistry. The relationship between the expression and activation of these proteins and peritoneal fluid (TNFα) concentrations, measured via ELISA, was examined. A subsequent in vitro analysis of TNFα treatment on the activation of IKKß and the effect on epithelial and stromal cell viability by its inhibition with PS1145 was also performed. MAIN RESULTS AND ROLE OF CHANCE: Levels of the phosphorylated IKKß complex in endometriotic lesions had a significant positive correlation with peritoneal fluid TNFα concentrations. Phosphorylated IKKß complex was more prevalent in peritoneal and deeply infiltrating endometriosis lesions compared with ovarian lesions. IKKß was present in both epithelial and stromal cells in all lesions but active IKKß was limited to epithelial cells. TNFα stimulated an increased expression of phosphorylated IKKß and the inhibition of this kinase with PS1145 significantly influenced ectopic epithelial cells viability but not eutopic epithelial cells, or endometrial stromal cells. LIMITATIONS, REASONS FOR CAUTION: In vitro analysis on epithelial cells was performed with immortalized cell lines and not primary cell cultures and only low sample numbers were available for the study. WIDER IMPLICATIONS OF THE FINDINGS: The regulation of aberrant signalling pathways represents a promising yet relatively unexplored area of endometriosis progression. The IKKß complex is activated by inflammation and is critical nodal point of numerous downstream kinase-signalling pathways, including NFκB (nuclear factor κB), mTOR (mammalian target of rapamycin) and BAD (Bcl2-antagonist of cell death). This study shows a significant relationship between peritoneal fluid TNFα and IKKß activation in epithelial cells that will have significant consequences for the continued survival of these cells at ectopic locations through the regulation of downstream pathways. LARGE SCALE DATA: None. STUDY FUNDING/COMPETING INTERESTS: The study was funded by the Swiss National Science Foundation (Grant Number 320030_140774). The authors have no conflict of interest to declare.

Inflammation influences steroid hormone receptors targeted by progestins in endometrial stromal cells from women with endometriosis.

Endometriosis is an estrogen-dependent disease characterised by the growth of endometrial epithelial and stromal cells outside the uterus creating a chronic inflammatory environment that further contributes to disease progression. The first choice treatment for endometriosis is currently progestin mediated hormone modulation. In addition to their progestogenic activity however, progestins also have the potential to bind to other nuclear receptors influencing their local activity on endometriotic cells. This local activity will be dependent on the steroid hormone receptor expression that occurs in endometrial cells in a chronic inflammatory environment. We therefore aimed to quantify receptors targeted by progestins in endometrial stromal cells after exposure to inflammation. Using primary endometrial stromal cells isolated from women with endometriosis we examined the mRNA and protein expression of the progesterone receptors A and B, membrane progesterone receptors 1 and 2, androgen receptors, mineralocorticoid receptors and glucocorticoid receptors after exposure to the inflammatory cytokines tumor necrosis factor α (TNFα) and interleukin 1ß (IL-1ß). The results indicate that both cytokines reduced the expression of progesterone receptors and increased the expression of the glucocorticoid receptors in the endometrial stromal cells. The change in expression of progestin targets in endometrial stromal cells in an inflammatory environment could contribute to the progesterone resistance observed in endometriotic cells and ultimately influence the design of hormonal therapies aimed at treating this disease.

Kinase signalling pathways in endometriosis: potential targets for non-hormonal therapeutics.

BACKGROUND: Endometriosis, the growth of endometrial tissue outside the uterine cavity, is associated with chronic pelvic pain, subfertility and an increased risk of ovarian cancer. Current treatments include the surgical removal of the lesions or the induction of a hypoestrogenic state. However, a reappearance of the lesion after surgery is common and a hypoestrogenic state is less than optimal for women of reproductive age. Additional approaches are required. Endometriosis lesions exist in a unique microenvironment characterized by increased concentrations of hormones, inflammation, oxidative stress and iron. This environment influences cell survival through the binding of membrane receptors and a subsequent cascading activation of intracellular kinases that stimulate a cellular response. Many of these kinase signalling pathways are constitutively activated in endometriosis. These pathways are being investigated as therapeutic targets in other diseases and thus may also represent a target for endometriosis treatment. METHODS: To identify relevant English language studies published up to 2015 on kinase signalling pathways in endometriosis, we searched the Pubmed database using the following search terms in various combinations; 'endometriosis', 'inflammation', 'oxidative stress', 'iron', 'kinase', 'NF kappa', 'mTOR', 'MAPK' 'p38', 'JNK', 'ERK' 'estrogen' and progesterone'. Further citing references were identified using the Scopus database and finally current clinical trials were searched on the clinicaltrials.gov trial registry. RESULTS: The current literature on intracellular kinases activated by the endometriotic environment can be summarized into three main pathways that could be targeted for treatments: the canonical IKKß/NFκB pathway, the MAPK pathways (ERK1/2, p38 and JNK) and the PI3K/AKT/mTOR pathway. A number of pharmaceutical compounds that target these pathways have been successfully trialled in in vitro and animal models of endometriosis, although they have not yet proceeded to clinical trials. The current generation of kinase inhibitors carry a potential for adverse side effects. CONCLUSIONS: Kinase signalling pathways represent viable targets for endometriosis treatment. At present, however, further improvements in clinical efficacy and the profile of adverse effects are required before these compounds can be useful for long-term endometriosis treatment. A better understanding of the molecular activity of these kinases, including the specific extracellular compounds that lead to their activation in endometriotic cells specifically should facilitate their improvement and could potentially lead to new, non-hormonal treatments of endometriosis.

Does dienogest influence the inflammatory response of endometriotic cells? A systematic review.

OBJECTIVE AND DESIGN: A systematic review of all literature was done to assess the ability of the progestin dienogest (DNG) to influence the inflammatory response of endometriotic cells. MAIN OUTCOME MEASURES: In vitro and in vivo studies report an influence of DNG on the inflammatory response in eutopic or ectopic endometrial tissue (animal or human). RESULTS: After strict inclusion criteria were satisfied, 15 studies were identified that reported a DNG influence on the inflammatory response in endometrial tissue. These studies identified a modulation of prostaglandin (PG) production and metabolism (PGE2, PGE2 synthase, cyclo-oxygenase-2 and microsomal PGE synthase-1), pro-inflammatory cytokine and chemokine production [interleukin (IL)-1ß, IL-6, IL-8, tumor necrosis factor-α, monocyte chemoattractant protein-1 and stromal cell-derived factor-1], growth factor biosynthesis (vascular endothelial growth factor and nerve growth factor) and signaling kinases, responsible for the control of inflammation. Evidence supports a progesterone receptor-mediated inhibition of the inflammatory response in PR-expressing epithelial cells. It also indicated that DNG inhibited the inflammatory response in stromal cells, however, whether this was via a PR-mediated mechanism is not clear. CONCLUSIONS: DNG has a significant effect on the inflammatory microenvironment of endometriotic lesions that may contribute to its clinical efficacy. A better understanding of the specific anti-inflammatory activity of DNG and whether this contributes to its clinical efficacy can help develop treatments that focus on the inhibition of inflammation while minimizing hormonal modulation.

Comparison of ovarian cancer markers in endometriosis favours HE4 over CA125.

Endometriosis is a gynaecological condition with an associated chronic inflammatory response. The ectopic growth of 'lesions', consisting of endometrial cells outside the uterine cavity, stimulates an inflammatory response initiating the activation of macrophages, and resulting in increased cytokine and growth factor concentrations in the peritoneal fluid (PF). Endometriosis­associated inflammation is chronic and long lasting. In patients with endometriosis, the risk of developing ovarian cancer within 10 years, particularly of the endometrioid or clear cell subtype, is increased 2.5­4 times. Endometriosis creates a peritoneal environment that exposes the affected endometriotic and the normal ovarian surface epithelial cells to agents that have been suggested to be involved in the pathogenesis of cancer. Concentrations of several cytokines and growth factors were increased in the PF of patients with endometriosis. The ovarian cancer marker, CA125, was one such growth factor; however, this remains to be confirmed. Human epididymis protein 4 (HE4) was detected at high concentrations in patients with ovarian cancer and was identified as the best biomarker for the detection of ovarian cancer. The present study determined the levels of HE4 and CA125 in the peritoneal fluid of 258 patients with and 100 control individuals without endometriosis attending the Department of Obstetrics and Gynaecology, University of Berne (Berne, Switzerland) between 2007 and 2014. The cases were subdivided into groups without hormonal treatment (n=107), or treated with combined oral contraceptives (n=45), continuous gestagens (n=56) or GnRH agonists (n=50). Both of these markers were significantly increased in the non­treated endometriosis samples compared with the control group. Hormone treatment with either of the three agents mentioned resulted in the concentration of CA125 returning to the control levels and the concentration of HE4 decreasing to below the control levels. CA125, however not HE4, significantly differed between the proliferative and secretory cycle phases. Since HE4 is sensitive to hormonal treatment and robust towards menstrual cycle variation, HE4 is potentially superior to CA125 as an endometriosis marker and therefore has greater potential as a marker for the identification of women at risk of developing ovarian cancer.

Anti-Müllerian hormone and progesterone levels produced by granulosa cells are higher when derived from natural cycle IVF than from conventional gonadotropin-stimulated IVF.

BACKGROUND: The study was designed to compare the effect of in vitro FSH stimulation on the hormone production and gene expression profile of granulosa cells (GCs) isolated from single naturally matured follicles obtained from natural cycle in vitro fertilization (NC-IVF) with granulosa cells obtained from conventional gonadotropin-stimulated IVF (c-IVF). METHODS: Lutein granulosa cells from the dominant follicle were isolated and cultured in absence or presence of recombinant FSH. The cultures were run for 48 h and six days. Messenger RNA (mRNA) expressions of anti-Müllerian hormone (AMH) and FSH receptor were measured by quantitative polymerase chain reaction (qPCR). AMH protein and progesterone concentration (P4) in cultured supernatant were measured by ELISA and RIA. RESULTS: Our results showed that the mRNA expression of AMH was significantly higher in GCs from NC- than from c-IVF on day 6 after treatment with FSH (1 IU/mL). The FSH stimulation increased the concentration of AMH in the culture supernatant of GCs from NC-IVF compared with cells from c-IVF. In the culture medium, the AMH level was correlated significantly and positively to progesterone concentration. CONCLUSIONS: Differences in the levels of AMH and progesterone released into the medium by cultured GC as well as in AMH gene expression were observed between GCs obtained under natural and stimulated IVF protocols. The results suggest that artificial gonadotropin stimulation may have an effect on the intra-follicular metabolism. A significant positive correlation between AMH and progesterone may suggest progesterone as a factor influencing AMH secretion.

Panels of cytokines and other secretory proteins as potential biomarkers of ovarian endometriosis.

Endometriosis is a gynecologic disease that is characterized by nonspecific symptoms and invasive diagnostics. To date, there is no adequate noninvasive method for the diagnosis of endometriosis. Although more than 100 potential biomarkers have been investigated in blood and/or peritoneal fluid, none of these has proven useful in clinical practice. The aim to find a suitable panel of biomarkers that would allow noninvasive diagnosis thus remains of interest. We evaluated the concentrations of 16 cytokines and other secretory proteins in serum and peritoneal fluid of 58 women with ovarian endometriosis (cases) and 40 healthy women undergoing sterilization or patients with benign ovarian cysts (controls) using multiplexed double fluorescence-based immunometric assay platform and enzyme-linked immunosorbent assay. Significantly higher concentrations of glycodelin-A were shown in serum, and significantly higher levels of glycodelin-A, IL-6, and IL-8, and lower levels of leptin were measured in the peritoneal fluid of cases versus controls. In serum, the best performance was shown by models that included the ratio of leptin/glycodelin-A and the ratio of ficolin 2/glycodelin-A, whereas in the peritoneal fluid the best models included the ratio of biglycan/leptin, regulated on activation normal T-cell expressed and secreted/IL-6 and ficolin-2/glycodelin-A, and IL-8 per milligram of total protein, all in combination with age. The models using serum and peritoneal fluid distinguished between ovarian endometriosis patients and controls regardless of the menstrual cycle phase with relatively high sensitivity (72.5% to 84.2%), specificity (78.4% to 91.2%), and area under the curve (0.85 to 0.90).

Detection of the pan neuronal marker PGP9.5 by immuno-histochemistry and quantitative PCR in eutopic endometrium from women with and without endometriosis.

PURPOSE: To assess endometrial gene as well as protein expression of neuroendocrine and supposedly endometriosis-associated product PGP9.5 and pain symptoms in women with endometriosis and controls undergoing laparoscopy, using molecular biological and immuno-histochemical approaches in the same patients. METHODS: Biopsy of eutopic endometrium from 29 patients by sharp curettage, and preparation of paraffin blocks. Determination of PGP9.5 gene expression and protein abundance using qPCR and immuno-histochemistry. RESULTS: qPCR; The PGP9.5 mRNA expression level between women with (N = 16) and without (N = 13) endometriosis was not different, regardless of pain symptoms or menstrual cycle phase. PGP9.5 expression was higher in women who reported pain compared to those who did not; however, this association was not statistically significant. The expression of PGP9.5 mRNA was higher in women with endometriosis and pain during the proliferative than in the secretory phase (P = 0.03). Furthermore, in the first half of the cycle, the abundance of the PGP9.5 transcript was also significantly higher in endometriosis patients compared to those without (P = 0.03). Immuno-histochemistry; Thirteen of the 16 endometriosis patients showed positive PGP9.5 immuno-reactivity in the endometrium, whereas no such signal was observed in women without endometriosis. The absolute number of nerve fibres per mm(2) in women with endometriosis was similar, regardless of the pain symptoms. CONCLUSIONS: PGP9.5 mRNA expression is increased in the proliferative phase of endometriotic women with pain. The presence of nerve fibres was demonstrated by a PGP9.5 protein signal in immuno-histochemistry and restricted to patients with endometriosis. Based on these results, however, there did not appear to be a direct association between the gene expression and protein abundance in women with and without endometriosis or those that experienced pain.

Inflammation and nerve fiber interaction in endometriotic pain.

Endometriosis is an extremely prevalent estrogen-dependent condition characterized by the growth of ectopic endometrial tissue outside the uterine cavity, and is often presented with severe pain. Although the relationship between lesion and pain remains unclear, nerve fibers found in close proximity to endometriotic lesions may be related to pain. Also, women with endometriosis pain develop central sensitization. Endometriosis creates an inflammatory environment and recent research is beginning to elucidate the role of inflammation in stimulating peripheral nerve sensitization. In this review, we discuss endometriosis-associated inflammation, peripheral nerve fibers, and assess their potential mechanism of interaction. We propose that an interaction between lesions and nerve fibers, mediated by inflammation, may be important in endometriosis-associated pain.

Phospholipase A2 group IIA is elevated in endometriomas but not in peritoneal fluid and serum of ovarian endometriosis patients.

Our previous gene expression analysis identified phospholipase A2 group IIA (PLA2G2A) as a potential biomarker of ovarian endometriosis. The aim of this study was to evaluate PLA2G2A mRNA and protein levels in tissue samples (endometriomas and normal endometrium) and in serum and peritoneal fluid of ovarian endometriosis patients and control women. One-hundred and sixteen women were included in this study: the case group included 70 ovarian endometriosis patients, and the control group included 38 healthy women and 8 patients with benign ovarian cysts. We observed 41.6-fold greater PLA2G2A mRNA levels in endometrioma tissue, compared to normal endometrium tissue. Using Western blotting, PLA2G2A was detected in all samples of endometriomas, but not in normal endometrium, and immunohistochemistry showed PLA2G2A-specific staining in epithelial cells of endometrioma paraffin sections. However, there were no significant differences in PLA2G2A levels between cases and controls according to ELISA of peritoneal fluid (6.0 ± 4.4 ng/ml, 6.6 ± 4.3 ng/ml; p = 0.5240) and serum (2.9 ± 2.1 ng/ml, 3.1 ± 2.2 ng/ml; p = 0.7989). Our data indicate that PLA2G2A is implicated in the pathophysiology of ovarian endometriosis, but that it cannot be used as a diagnostic biomarker.

Correlation between altered central pain processing and concentration of peritoneal fluid inflammatory cytokines in endometriosis patients with chronic pelvic pain.

Translational research has not yet elucidated whether alterations in central pain processes are related to peripheral inflammatory processes in chronic pain patients. We tested the hypothesis that the concentration of cytokines in the peritoneal fluid of endometriosis patients with chronic pain correlate with parameters of hyperexcitability of the nociceptive system. The concentrations of 15 peritoneal fluid cytokines were measured in 11 patients with chronic pelvic pain and a diagnosis of endometriosis. Six parameters assessing central pain processes were recorded. Positive correlations between concentration of some cytokines in the peritoneal fluid and amplification of central pain processing were found. The results suggest that inflammatory mechanisms may be important in the pathophysiology of altered central pain processes and that cytokines produced in the environment of endometriosis could act as mediators between the peripheral lesion and changes in central nociceptive processes.

Increased levels of biglycan in endometriomas and peritoneal fluid samples from ovarian endometriosis patients.

In our previous low-density-array gene-expression analysis we found an increased expression of biglycan gene in ovarian endometriosis patients. In the present study we evaluated biglycan expression at the protein level in tissue, serum and peritoneal fluid (PF) from ovarian endometriosis patients, patients with benign ovarian cysts and healthy women. Twenty samples of endometriomas and 27 of control tissues (benign ovarian cysts and eutopic endometrium of healthy women) were obtained laparoscopically or by curettage. Serum and PF samples were collected from 56 ovarian endometriosis patients and 40 controls (patients with benign cysts and healthy women). Tissue biglycan levels and serum and PF biglycan concentrations were determined by Western blotting and ELISA, respectively. Biglycan was detected in endometriomas and in benign cysts tissues but differed in glycosylation levels. The PF biglycan concentrations were significantly increased in ovarian endometriosis patients (mean ± SD=220.3 ± 190.5 pg/mg protein) compared to the whole control group (101.9 ± 94.7 pg/mg protein, p<0.001), while serum concentrations did not differ significantly. Biglycan appears to be involved in ovarian pathologies and probably has different roles in benign cysts as compared to ovarian endometriomas.