Characterization of endometriosis-associated immune cell infiltrates (EMaICI)

Clotrimazole is effective for the regression of endometriotic implants in a Wistar rat experimental model of endometriosis

The present work aimed to evaluate molecular, angiogenic and inflammatory changes induced by clotrimazole (CTZ) on endometriosis lesions. For this, thirty female Wistar rats with surgically implanted autologous endometrium were treated with CTZ or vehicle (200 mg/kg) via esophageal gavage for 15 consecutive days. CTZ treatment significantly decreased the growth and the size of the implants, and histological examination indicated regression and atrophy, with no toxicity to the animals. The levels of the angiogenic markers VEGF and VEGFR-2 were significantly decreased in CTZ group. The treatment also promotes a reduction on PGE₂ and TNF-α levels. All these effects involve the amelioration of ERK1/2, Akt, AMPK and PERK signaling upon CTZ treatment. In conclusion, CTZ promoted an overall amelioration of endometriosis in a rat model due to the anti-angiogenic properties of the drug. Therefore, our results support the proposal of a clinical trial using CTZ for the treatment of endometriosis.

Genetic Variation at Chromosome 2q13 and Its Potential Influence on Endometriosis Susceptibility Through Effects on the IL-1 Family

Endometriosis is characterized by the growth of epithelial and stromal cells outside the uterine cavity. It has a complex etiology and affects ∼10% of reproductive age women. It is accompanied by a chronic inflammatory response with substantial evidence to indicate genetic susceptibility. The causal genes and their pathways leading to endometriosis, however, are still unknown. Recently, genomewide association studies on endometriosis identified 14 genomic risk loci in women of European and Japanese ancestry. It is becoming increasingly clear that these risk regions are intergenic and thus contribute to disease susceptibility through regulatory mechanisms, most likely mediated through regulation of genes within a restricted distance from the risk variants. One endometriosis risk locus has been detected at chromosome 2q13 within an inflammatory-rich region of gene transcripts and thus may play a role in the inflammation component of the disease. We carried out detailed analysis of the genomic region 250 kb on either side of sentinel SNP rs10167914 and identified 21 transcripts which contained 6 interleukin (IL)-1 family genes, 3 previously reported coding genes that have a relationship to inflammation, 4 novel coding, or pseudogenes, and 8 noncoding RNA transcripts. Through an extensive literature search, we examined the roles these genes and their resultant proteins play in endometriosis pathogenesis. The results suggest alteration in the expression the IL-1 family transcripts either alone or as a complex milieu could have a significant influence on endometriosis and should be prioritized for future study on the implications of inflammation on endometriotic lesions.

Effects of acupuncture for the treatment of endometriosis-related pain: A systematic review and meta-analysis

BACKGROUND

Endometriosis is a multifactorial, oestrogen-dependent, inflammatory, gynaecological condition that can result in long-lasting visceral pelvic pain and infertility. Acupuncture could be an effective treatment for endometriosis and may relieve pain. Our aim in the present study was to determine the effectiveness of acupuncture as a treatment for endometriosis-related pain.

METHODS

In December 2016, six databases were searched for randomised controlled trials that determined the effectiveness of acupuncture in the treatment of endometriosis-related pain. Ultimately, 10 studies involving 589 patients were included. The main outcomes assessed were variation in pain level, variation in peripheral blood CA-125 level, and clinical effective rate. All analyses were performed using comprehensive meta-analysis statistical software.

RESULTS

Of the 10 studies included, only one pilot study used a placebo control and assessed blinding; the rest used various controls (medications and herbs), which were impossible to blind. The sample sizes were small in all studies, ranging from 8 to 36 patients per arm. The mean difference (MD) in pain reduction (pre- minus post-interventional pain level-measured on a 0-10-point scale) between the acupuncture and control groups was 1.36 (95% confidence intervals [CI] = 1.01-1.72, P<0.0001). Acupuncture had a positive effect on peripheral blood CA-125 levels, as compared with the control groups (MD = 5.9, 95% CI = 1.56-10.25, P = 0.008). Similarly, the effect of acupuncture on clinical effective rate was positive, as compared with the control groups (odds ratio = 2.07; 95% CI = 1.24-3.44, P = 0.005).

CONCLUSIONS

Few randomised, blinded clinical trials have addressed the efficacy of acupuncture in treating endometriosis-related pain. Nonetheless, the current literature suggests that acupuncture reduces pain and serum CA-125 levels, regardless of the control intervention used. To confirm these findings, additional, blinded studies with proper controls and adequate sample sizes are needed.

The crosstalk between endometrial stromal cells and macrophages impairs cytotoxicity of NK cells in endometriosis by secreting IL-10 and TGF-β

The dysfunction of NK cells in women with endometriosis (EMS) contributes to the immune escape of menstrual endometrial fragments refluxed into the peritoneal cavity. The reciprocal communications between endometrial stromal cells (ESCs) and lymphocytes facilitate the development of EMS. However, the mechanism of these communications on cytotoxicity of natural killer (NK) cells in endometriotic milieus is still largely unknown. To imitate the local immune microenvironment, the co-culture systems of ESCs from patients with EMS and monocyte-derived macrophages or of ESCs, macrophages and NK cells were constructed. The cytokine levels in the co-culture unit were evaluated by ELISA. The expression of functional molecules in NK cells was detected by flow cytometry (FCM). The NK cell behaviors in vitro were analyzed by cell counting kit-8 and cytotoxic activation assays. After incubation with ESCs and macrophages, the expression of CD16, NKG2D, perforin and IFN-γ, viability and cytotoxicity of NK cells were significantly downregulated. The secretion of interleukin (IL)-1β, IL-10 and transforming growth factor (TGF)-β in the co-culture system of ESCs and macrophages was increased. Exposure with anti-IL-10 receptor β neutralizing antibody (αhIL-10Rβ) or αTGF-β could partly reverse these effects of ESCs and macrophages on NK cells in vitro These results suggest that the interaction between macrophages and ESCs downregulates cytotoxicity of NK cells possibly by stimulating the secretion of IL-10 and TGF-β, and may further trigger the immune escape of ectopic fragments and promote the occurrence and the development of EMS.

The role of the B lymphocytes in endometriosis: A systematic review

The physiopathology of endometriosis is not completely understood and its progression is associated with a local and systemic inflammatory reaction. It is important to clarify the potential role of the immune system to better understand its implication in the pathogenesis of endometriosis, which includes the study of the role of B cells and antibodies. The aim of this study was to review the literature about the role of B lymphocytes in endometriosis. A search for "endometriosis", "B cells" and "B lymphocytes" in databases resulted in 140 citations; after applying inclusion and exclusion criteria, a total of 22 studies were assessed. The analyzed samples in the studies varied and different markers and techniques were used by the authors to evaluate the direct or indirect role of B lymphocytes in endometriosis. Most studies demonstrated increased number and/or activation of B cells while seven studies found no difference and two studies showed decreased number of B cells. Increased B lymphocytes and excessive production of autoantibodies in endometriosis have been described in the literature, but their role in the development of the disease is not well understood. Moreover, the association of these factors with clinical symptoms, location and severity of the disease has not been investigated. Further studies are necessary to clarify the role of B cells in the development of endometriosis and propose new therapeutic strategies such as the use of drugs that target these cells.

The Expression of Toll-like receptors in eutopic and ectopic endometrium and its implication in the inflammatory pathogenesis of adenomyosis

In this study, we investigated the expression profiles of Toll-like receptors(TLRs) in eutopic endometrium(EU) and ectopic endometrium(EC) and its implication in the inflammatory pathogenesis of adenomyosis. Thirty adenomyosis patients who underwent laparoscopy were recruited in this study. We tested the mRNA and protein expression of TLRs, and the mRNA expression of IL-6 and IL-8 in EU and EC of adenomyosis patients, and control endometrium without adenomyosis(CE). We found that the mRNA expression of IL-6 and IL-8 in EU was significantly higher than that in CE, and was the highest in EC (P < 0.01). The mRNA and protein expression of TLRs were higher in EU, with the expression of TLR1-6, 8 and 9 being significantly higher in EU than in CE, and were the highest in EC (except TLR6) (P < 0.05 or P < 0.01). Pearson correlation analysis showed that the expression of TLR1, 2, 4, 5 and 9 in EU and EC was positively correlated with that of IL-6 and IL-8 (P < 0.00139). This study suggested that adenomyosis was a state of inflammatory pathology. High expression of TLRs in EU and EC were positively correlated with IL-6 and IL-8, which may be involved in the inflammatory pathogenesis of adenomyosis.

Macrophage and nerve interaction in endometriosis

Dysregulation of the immune system in endometriotic milieus has been considered to play a pivotal role in the pathogenesis of endometriosis. Macrophage recruitment and nerve fiber infiltration are the two major characteristics of this aberrant immune environment. First, the recruitment of macrophages and their polarization phenotype within the endometriotic lesion have been demonstrated to facilitate the development and maintenance of endometriosis. M1 phenotype of macrophages has the capacity to secrete multiple cytokines for inflammatory response, while M2 macrophage possesses an opposite property that can mediate the process of immunosuppression and neuroangiogenesis. Upon secretion of multiple abnormal signal molecules by the endometriotic lesion, macrophages could alter their location and phenotype. These changes facilitate the accommodation of the aberrant microenvironment and the exacerbation of disease progression. Second, the infiltration of nerve fibers and their abnormal distribution are proved to be involved in the generation of endometriosis-associated pain and inflammatory response. An imbalance in sensory and sympathetic innervation and the abnormal secretion of different cytokines could mediate neurogenesis and subsequent peripheral neuroinflammation in endometriosis. Although endometriosis creates an inflammatory milieu promoting macrophage infiltration and an imbalanced innervation, interaction between macrophages and nerve fibers in this process remains unknown. The aim of this review is to highlight the role of macrophage and nerve interaction in endometriosis, where macrophage recruitment and neurogenesis can be the underlying mechanism of neuroinflammation and pathogenesis of endometriosis.

Research development of a new GnRH antagonist (Elagolix) for the treatment of endometriosis: a review of the literature

PURPOSE

Limitated studies have reported the efficacy of GnRH antagonist on endometriosis symptoms. The aim of our study was to review all available trials to investigate the medical treatment of endometriosis with only GnRH antagonists, with special attention to pharmacodynamic activity, safety, and efficacy.

METHODS

Pub Med and Sciencedirect database were searched using terms of "endometriosis treatment", "GnRH antagonist", and "Elagolix". The search was limited to clinical studies published in English. Title and abstract were screened to identify relevant articles.

RESULTS

Five studies covering use of GnRH antagonist were found. A phase 1 study evaluated the safety, pharmacokinetics, and inhibitory effects on gonadotropins and estradiol of single dose and 7 day elagolix administration to healthy premenopausal women; two phase II studies evaluated efficacy in patient with endometriosis. Moreover, there are two Phase III clinical trials just completed.

CONCLUSION

GnRH antagonists may have the advantage of oral administration and lower incidence of adverse events. Currently, only Phase II studies have been published demonstrating promising results in terms of efficacy, safety, and tolerability. From the results of the phase III studies, elagolix may become a valuable addition to the armamentarium of pharmacological agents to treat endometriosis-related pain.