Elevated levels of adrenomedullin in eutopic endometrium and plasma from women with endometriosis

Endometriosis-Related Chronic Pelvic Pain

Endometriosis, which is the presence of endometrial stroma and glands outside the uterus, is one of the most frequently diagnosed gynecologic diseases in reproductive women. Patients with endometriosis suffer from various pain symptoms such as dysmenorrhea, dyspareunia, and chronic pelvic pain. The pathophysiology for chronic pain in patients with endometriosis has not been fully understood. Altered inflammatory responses have been shown to contribute to pain symptoms. Increased secretion of cytokines, angiogenic factors, and nerve growth factors has been suggested to increase pain. Also, altered distribution of nerve fibers may also contribute to chronic pain. Aside from local contributing factors, sensitization of the nervous system is also important in understanding persistent pain in endometriosis. Peripheral sensitization as well as central sensitization have been identified in patients with endometriosis. These sensitizations of the nervous system can also explain increased incidence of comorbidities related to pain such as irritable bowel disease, bladder pain syndrome, and vulvodynia in patients with endometriosis. In conclusion, there are various possible mechanisms behind pain in patients with endometriosis, and understanding these mechanisms can help clinicians understand the nature of the pain symptoms and decide on treatments for endometriosis-related pain symptoms.

Infertility workup: identifying endometriosis

Endometriosis was classically diagnosed during diagnostic laparoscopies, which used to be routinely performed up until a decade ago or so. This practice fitted with the long-held belief that surgery was the gold standard for diagnosing endometriosis. Today, the abandon of routine diagnostic laparoscopies-in favor of assisted reproductive technology-first therapeutic approaches-has created a void for diagnosing endometriosis. Modern-day imaging techniques-ultrasound and magnetic resonance imaging-when used with a systematic approach have offered a reliable replacement option for diagnosing endometriosis. In infertility, endometriosis should be identified or excluded on the basis of past history or confirmation or exclusion suspicion on the basis of history and/or physical examination.

TET1 may contribute to hypoxia-induced epithelial to mesenchymal transition of endometrial epithelial cells in endometriosis

Background

Endometriosis (EMs) is a non-malignant gynecological disease, whose pathogenesis remains to be clarified. Recent studies have found that hypoxia induces epithelial-mesenchymal transition (EMT) as well as epigenetic modification in EMs. However, the relationship between EMT and demethylation modification under hypoxia status in EMs remains unknown.

Methods

The expression of N-cadherin, E-cadherin and TET1 in normal endometria, eutopic endometria and ovarian endometriomas was assessed by immunohistochemistry and immunofluorescence double staining. 5-hmC was detected by fluorescence-based ELISA kit using a specific 5-hmC antibody. Overexpression and inhibition of TET1 or hypoxia-inducible factor 2α (HIF-2α) were performed by plasmid and siRNA transfection. The expression of HIF-2α, TET1 and EMT markers in Ishikawa (ISK) cells (widely used as endometrial epithelial cells) was evaluated by western blotting. The interaction of HIF-2α and TET1 was analyzed by chromatin immunoprecipitation.

Results

Demethylation enzyme TET1 (ten-eleven translocation1) was elevated in glandular epithelium of ovarian endometrioma, along with the activation of EMT (increased expression of N-cadherin, and decreased expression of E-cadherin) and global increase of epigenetic modification marker 5-hmC(5-hydroxymethylcytosine). Besides, endometriosis lesions had more TET1 and N-cadherin co-localized cells. Further study showed that ISK cells exhibited enhanced EMT, and increased expression of TET1 and HIF-2α under hypoxic condition. Hypoxia-induced EMT was partly regulated by TET1 and HIF-2α. HIF-2α inhibition mitigated TET1 expression changes provoked by hypoxia.

Conclusions

Hypoxia induces the expression of TET1 regulated by HIF-2α, thus may promote EMT in endometriosis.

Adrenomedullin insufficiency alters macrophage activities in fallopian tube: a pathophysiologic explanation of tubal ectopic pregnancy

Ectopic pregnancy is the major cause of maternal morbidity and mortality in the first trimester of pregnancy. Tubal ectopic pregnancy (TEP) accounts for nearly 98% of all ectopic pregnancies. TEP is usually associated with salpingitis but the underlying mechanism in salpingitis leading to TEP remains unclear. Adrenomedullin (ADM) is a peptide hormone abundantly expressed in the fallopian tube with potent anti-inflammatory activities. Its expression peaks at the early luteal phase when the developing embryo is being transported through the fallopian tube. In the present study, we demonstrated reduced expression of ADM in fallopian tubes of patients with salpingitis and TEP. Using macrophages isolated from the fallopian tubes of these women, our data revealed that the salpingistis-associated ADM reduction contributed to aggravated pro-inflammatory responses of the tubal macrophages resulting in production of pro-inflammatory and pro-implantation cytokines IL-6 and IL-8. These cytokines activated the expression of implantation-associated molecules and Wnt signaling pathway predisposing the tubal epithelium to an adhesive and receptive state for embryo implantation. In conclusion, this study provided evidence for the role of ADM in the pathogenesis of TEP through regulating the functions of tubal macrophages.

Autonomic nervous system and inflammation interaction in endometriosis-associated pain

Endometriosis is a chronic inflammatory disease. Pain is the most common symptom in endometriosis. Endometriosis-associated pain is caused by inflammation, and is related to aberrant innervation. Although the specific mechanism between endometriosis-associated pain and the interaction of aberrant innervation and inflammation remains unclear, many studies have confirmed certain correlations between them. In addition, we found that some chronic inflammatory autoimmune diseases (AIDs) such as inflammatory bowel disease (IBD) and rheumatoid arthritis (RA) share similar characteristics: the changes in dysregulation of inflammatory factors as well as the function and innervation of the autonomic nervous system (ANS). The mechanisms underlying the interaction between the ANS and inflammation have provided new advances among these disorders. Therefore, the purpose of this review is to compare the changes in inflammation and ANS in endometriosis, IBD, and RA; and to explore the role and possible mechanism of sympathetic and parasympathetic nerves in endometriosis-associated inflammation by referring to IBD and RA studies to provide some reference for further endometriosis research and treatment.

Higher adrenomedullin levels during implantation are associated with successful pregnancy

Aim

To determine how the adrenomedullin (ADM) level in a woman's serum on the day of embryo transfer affects pregnancy results.

Materials & Methods

Women who had undergone frozen embryo transfer between July 2018 and February 2019 were prospectively included in the study. The relation between the level of ADM and pregnancy result was examined after taking a sample of serum from each patients on the same day as the transfer.

Results

The results revealed that the ADM levels in patients who became pregnant were higher, but not to a statistically significant level.

Conclusion

Adrenomedullin is an important molecule for human embryo implantation.

Lymphatic Function and Dysfunction in the Context of Sex Differences

Endothelial cells are the building blocks of the blood vascular system and exhibit well-characterized sexually dimorphic phenotypes with regard to chromosomal and hormonal sex, imparting innate genetic and physiological differences between male and female vascular systems and cardiovascular disease. However, even though females are predominantly affected by disorders of lymphatic vascular function, we lack a comprehensive understanding of the effects of sex and sex hormones on lymphatic growth, function, and dysfunction. Here, we attempt to comprehensively evaluate the current understanding of sex as a biological variable influencing lymphatic biology. We first focus on elucidating innate and fundamental differences between the sexes in lymphatic function and development. Next, we delve into lymphatic disease and explore the potential underpinnings toward bias prevalence in the female population. Lastly, we incorporate more broadly the role of the lymphatic system in sex-biased diseases such as cancer, cardiovascular disease, reproductive disorders, and autoimmune diseases to explore whether and how sex differences may influence lymphatic function in the context of these pathologies.

Fibrinogen alpha chain is up-regulated and affects the pathogenesis of endometriosis

RESEARCH QUESTION

In the group's previous study, fibrinogen alpha chain (FGA) was identified as an up-regulated differential protein that was highly expressed in women with endometriosis. The current study investigated the expression and effects of FGA in endometriosis. It also evaluated the effects of FGA on human endometrial stromal cells and studied the possible mechanism.

DESIGN

This was a cross-sectional analysis of FGA expression in plasma and endometrial tissue of matched eutopic and ectopic samples from women with endometriosis undergoing laparoscopic surgery and samples from women without endometriosis. Forty-four patients with endometriosis and 32 healthy control subjects who donated plasma for FGA analysis, including 26 matched cases of eutopic and ectopic endometria from endometriosis patients and 22 endometria from healthy control subjects, were analysed. The effects of FGA were studied in a human endometrial stromal cell line after transfection with FGA short interfering RNA (siRNA).

RESULTS

FGA concentrations in serum and expression in eutopic and ectopic endometrial tissue were significantly higher in women with endometriosis than controls (P < 0.05 and P < 0.01 respectively), whereas FGA expression was not significantly different in eutopic compared with ectopic endometrial tissues from the same patients. High FGA concentrations in serum were related to disease stage and ovarian involvement, but were not affected by age and menstrual cycle. The knockdown of FGA expression by FGA siRNA inhibited hEM15A cellular adhesion, migration and invasion, and attenuated matrix metalloproteinase-2 (MMP-2) expression.

CONCLUSIONS

High FGA expression in endometriosis was closely related to disease severity and affected cell adhesion, migration and invasion, which might play an important role in the pathogenesis of endometriosis.