The Dysregulated IL-23/TH17 Axis in Endometriosis Pathophysiology

Endometriosis is a chronic inflammatory disease in which endometrial-like tissue grows ectopically, resulting in pelvic pain and infertility. IL-23 is a key contributor in the development and differentiation of TH17 cells, driving TH17 cells toward a pathogenic profile. In a variety of inflammatory and autoimmune disorders, TH17 cells secrete proinflammatory cytokines, including IL-17, contributing to disease pathophysiology. Our studies and others have implicated IL-17 and TH17 cell dysregulation in endometriosis, which is associated with disease severity. In this article, we address whether IL-23-driven TH17 cells contribute to cardinal features of lesion proliferation, vascularization, and inflammation in endometriosis using patient samples, representative cell lines, and our established mouse model of endometriosis. The results indicated dysregulated expression of key genes in the IL-23/TH17 axis in patient ectopic and eutopic endometrial samples and increased IL-23 protein in patient plasma compared with controls. In vitro studies using primary human TH cells determined that rIL-23 mixture treatment increased pathogenic TH17 cell frequency. Similarly, rIL-23 treatment of cell lines (12Z cells, EECCs, HUVECs, and hESCs) representative of the endometriotic lesion microenvironment increased cytokines and growth factors, which play a role in lesion establishment and maintenance. In a syngeneic mouse model of endometriosis, rIL-23 treatment altered numbers of myeloid and T cell subsets in peritoneal fluid and increased giant cells within the lesion. Lesions from rIL-23-treated mice did not reveal significant alterations in proliferation/vascularization, although trends of increased proliferation and vascularization were observed. Collectively, these findings provide insights into the impact of the IL-23/TH17 axis on local immune dysfunction and broadly on endometriosis pathophysiology.

The dysregulation of leukemia inhibitory factor and its implications for endometriosis pathophysiology

Endometriosis is an estrogen dominant, chronic inflammatory disease characterized by the growth of endometrial-like tissue outside of the uterus. The most common symptoms experienced by patients include manifestations of chronic pelvic pain- such as pain with urination, menstruation, or defecation, and infertility. Alterations to Leukemia Inhibitory Factor (LIF), a cytokine produced by the luminal and glandular epithelium of the endometrium that is imperative for successful pregnancy, have been postulated to contribute to infertility. Conditions such as recurrent implantation failure, unexplained infertility, and infertility associated diseases such as adenomyosis and endometriosis, have demonstrated reduced LIF production in the endometrium of infertile patients compared to fertile counterparts. While this highlights the potential involvement of LIF in infertility, LIF is a multifaceted cytokine which plays additional roles in the maintenance of cell stemness and immunomodulation. Thus, we sought to explore the implications of LIF production within ectopic lesions on endometriosis pathophysiology. Through immunohistochemistry of an endometrioma tissue microarray and ELISA of tissue protein extract and peritoneal fluid samples, we identify LIF protein expression in the ectopic lesion microenvironment. Targeted RT qPCR for LIF and associated signaling transcripts, identify LIF to be significantly downregulated in the ectopic tissue compared to eutopic and control while its receptor, LIFR, is upregulated, highlighting a discordance in ectopic protein and mRNA LIF expression. In vitro treatment of endometriosis representative cell lines (12Z and hESC) with LIF increased production of immune-recruiting cytokines (MCP-1, MCP-3) and the angiogenic factor, VEGF, as well as stimulated tube formation in human umbilical vein endothelial cells (HUVECs). Finally, LIF treatment in a syngeneic mouse model of endometriosis induced both local and peripheral alterations to immune cell phenotypes, ultimately reducing immunoregulatory CD206+ small peritoneal macrophages and T regulatory cells. These findings suggest that LIF is present in the ectopic lesions of endometriosis patients and could be contributing to lesion vascularization and immunomodulation.

Estrogen mediates inflammatory role of mast cells in endometriosis pathophysiology

Endometriosis is an estrogen dependent, chronic inflammatory disease characterized by the growth of endometrial lining outside of the uterus. Mast cells have emerged as key players in regulating not only allergic responses but also other mechanisms such as angiogenesis, fibrosis, and pain. The influence of estrogen on mast cell function has also been recognized as a potential factor driving disease pathophysiology in number of allergic and chronic inflammatory conditions. However, precise information is lacking on the cross talk between endocrine and immune factors within the endometriotic lesions and whether that contributes to the involvement of mast cells with disease pathophysiology. In this study, we observed a significant increase in mast cell numbers within endometriotic lesions compared to matched eutopic endometrium from the same patients. Compared to eutopic endometrium, endometriotic lesions had significantly higher levels of stem cell factor (SCF), a potent growth factor critical for mast cell expansion, differentiation, and survival for tissue resident mast cells. Targeted mRNA Q-PCR array revealed that the endometriotic lesions harbour microenvironment (upregulation of CPA3, VCAM1, CCL2, CMA1, CCR1, and KITLG) that is conducive to mast cells recruitment and subsequent differentiation. To examine cross-talk of mast cells within the endometriotic lesion microenvironment, endometriotic epithelial cells (12Z) and endometrial stromal cells (hESC) incubated with mast cell-conditioned media showed significantly increased production of pro-inflammatory and chemokinetic cytokines. To further understand the impact of estrogen on mast cells in endometriosis, we induced endometriosis in C57BL/6 mice. Mature mast cells were significantly higher in peritoneal fluid of estrogen-treated mice compared to untreated mice within the sham operated groups. Mouse endometriotic lesion tissue revealed several genes (qRT-PCR) relevant in mast cell biology significantly upregulated in the estrogen treated, endometriosis-induced group compared to control endometrium. The endometriotic lesions from estrogen treated mice also had significantly higher density of Alcian blue stained mast cells compared to untreated lesions or control endometrium. Collectively, these findings suggest that endometriotic lesions provide a microenvironment necessary for recruitment and differentiation of mast cells. In turn, mast cells potentially release pro-inflammatory mediators that contribute to chronic pelvic pain and endometriosis disease progression.

T helper 17 axis and endometrial macrophage disruption in menstrual effluent provides potential insights into the pathogenesis of endometriosis

OBJECTIVE

To identify immune cells, cytokines, and immune cell transcriptome in the menstrual effluent (ME) of women with endometriosis compared with that of healthy donors.

DESIGN

Live immune cells were isolated from human ME samples and were analyzed by flow cytometry to identify various immune cell populations. Selected cytokines from the same patients were evaluated using multiplex cytokine analyses. The transcriptome of the immune cell population was subsequently profiled using NanoString nCounter's PanCancer Immune panel.

SETTING

Academic institution.

PATIENT(S)

Surgically confirmed endometriosis patients (n = 14) and healthy fertile donors (n = 19).

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

In-depth immune cell profiling of ME obtained from women with endometriosis compared with that of healthy donors.

RESULT(S)

ME analysis revealed that the number of T helper 17 (T_H17) cells was significantly lower in patients with endometriosis compared with that of healthy donors; the number of macrophages was also lower (P=.06) in the former. Multiplex cytokine analysis revealed significantly lower transforming growth factor α in the ME "serum" of patients with endometriosis. Transcriptomic analysis of CD45⁺ cells revealed 47 differentially expressed genes, mainly associated with the T_H17 axis (IL10, IL23A, and IL6), as well as genes associated with macrophage signaling/activation (CD74, CD83, CXCL16, and CCL3).

CONCLUSION(S)

We demonstrate for the first time that the levels of T_H17 axis, macrophages, and transforming growth factor α were altered in the ME of women with endometriosis compared with that of healthy donors. These findings shed light on the potential immune pathways that could partly explain the pathogenesis and progression of endometriosis. Future large-scale studies on ME samples are warranted to exploit the use of these markers to study the pathogenesis of endometriosis.

IL-33 activates group 2 innate lymphoid cell expansion and modulates endometriosis

Chronic inflammation and localized alterations in immune cell function are suspected to contribute to the progression of endometriosis and its associated symptoms. In particular, the alarmin IL-33 is elevated in the plasma, peritoneal fluid, and endometriotic lesions from patients with endometriosis; however, the exact role of IL-33 in the pathophysiology of endometriosis is not well understood. In this study, we demonstrate, in both humans and a murine model, that IL-33 contributes to the expansion of group 2 innate lymphoid cells (ILC2s), and this IL-33–induced ILC2 expansion modulates the endometriosis lesion microenvironment. Importantly, we show that IL-33 drives hallmarks of severe endometriosis, including elevated inflammation, lesion proliferation, and fibrosis, and that this IL-33–induced aggravation is mediated by ILC2s. Finally, we demonstrate the functionality of IL-33 neutralization as a promising and potentially novel therapeutic avenue for treating the debilitating symptoms of endometriosis.

Implications of dysregulated endogenous cannabinoid family members in the pathophysiology of endometriosis

OBJECTIVE

To determine the involvement of the endocannabinoid (EC) family member in the pathophysiology of endometriosis (EMS).

DESIGN

Mass spectrometry analysis of plasma and tissue samples from patients with EMS, controls, and a mouse model of EMS and messenger RNA and immunohistochemistry analysis of the samples from patients with EMS and controls.

SETTING

Academic teaching hospital and university.

PATIENT(S)

Patients with EMS and healthy fertile control subjects.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Endocannabinoid analysis in patient plasma, EMS lesions, and healthy endometrial samples.

RESULT(S)

Circulating ECs were detected in the plasma samples, whereas no significant changes were observed in patients with EMS compared with healthy fertile controls. However, the palmitoylethanolamide levels were significantly higher in the EMS lesions than in the endometrium from patients with EMS. Similarly, genes involved in the EC signaling pathways were differentially expressed in the EMS lesions. Analysis of cannabinoid 1 and 2 receptors in the EMS lesions revealed a significantly lower cannabinoid 2 receptor expression, whereas no significant changes were observed in cannabinoid 1 receptor expression compared with those in the endometrium from both patients with EMS and healthy fertile controls. The palmitoylethanolamide levels were significantly elevated in plasma from EMS mice compared with that from sham controls and in EMS lesions compared with uterine samples.

CONCLUSION(S)

Together, we provide evidence toward dysregulation of members of the ECs in both patients with EMS and the mouse model of EMS. These findings will advance the knowledge of the role of ECs in EMS and their potential implications as therapeutic targets.

Synthetic Cannabinoid Agonist WIN 55212-2 Targets Proliferation, Angiogenesis, and Apoptosis via MAPK/AKT Signaling in Human Endometriotic Cell Lines and a Murine Model of Endometriosis

Endometriosis (EM) is characterized by the growth of endometrium-like tissue outside the uterus, leading to chronic inflammation and pelvic pain. Lesion proliferation, vascularization, and associated inflammation are the hallmark features of EM lesions. The legalization of recreational cannabinoids has garnered interest in the patient community and is contributing to a greater incidence of self medication; however, it remains unknown if cannabinoids possess marked disease-modifying properties. In this study, we assess the effects of synthetic cannabinoid, WIN 55212-2 (WIN 55), in EM-representative in vitro and in vivo syngeneic mouse models. WIN 55 reduced proliferation and angiogenesis in vitro, via MAPK/Akt-mediated apoptosis. These findings were corroborated in a mouse model of EM, where we found reduced TRPV1 expression in the dorsal root ganglia of the EM mouse model exposed to WIN 55, suggesting reduced signaling of pain stimuli. Ultimately, these pieces of evidence support the use of cannabinoid receptor agonists as a potential therapeutic intervention for EM associated pain and inflammation.

IL-33 activates ILC2 expansion and modulates endometriosis

Introduction: Chronic inflammation drives endometriosis (EM) and its associated symptoms. Interleukin (IL)-33, has gained therapeutic interest as it is elevated in the plasma, peritoneal fluid (PF), and lesions of EM patients. However, how IL-33 contributes to EM is largely unknown. For the first time, we demonstrate, using both human samples and murine models, that IL-33 expands local group 2 innate lymphoid cells (ILC2s) and that IL-33 activated ILC2s modulate hallmark features of EM.

Methods:

We identified ILC2s (CD45+Lin−CRTH2+CD127+ST2+) in the PF of EM patients using flow cytometry. Using immunofluorescence, we determine whether IL-33 forms epithelial or stromal cell niches within the EM lesion. Then, using our well established EM model, we induced EM in female C57Bl/6 mice and treated with PBS or IL-33. Hallmark features of EM were assessed including inflammation (using multiplex cytokine analysis), immune cell profiling (using flow cytometry), and lesion architecture (using immunohistochemistry and Nanostring transcriptomic profiling). To establish cause and effect, we treated ILC2 deficient mice with PBS (n=5) or IL-33 (n=5). Unpaired t-tests and one-way ANOVAs were done when appropriate.

Results/Discussion:

In humans, ILC2s are present and elevated in EM patients (n=5) compared to healthy donors (n=3) and IL-33 colocalized with both epithelial and stromal cells within the EM lesion. Using murine models, IL-33 drove hallmark features of EM including increased inflammation, alterations in PF immune cells (including eosinophils, T cells, macrophages and ILC2s), as well as increased lesion proliferation, neurogenesis and fibrosis. Using ILC2 deficient mice, we show that IL-33 induced pathology is ILC2 dependent.

Insights Into Extracellular Vesicle/Exosome and miRNA Mediated Bi-Directional Communication During Porcine Pregnancy

Spontaneous fetal loss is one of the most important challenges that commercial pig industry is still facing in North America. Research over the decade provided significant insights into some of the associated mechanisms including uterine capacity, placental efficiency, deficits in vasculature, and immune-inflammatory alterations at the maternal-fetal interface. Pigs have unique epitheliochorial placentation where maternal and fetal layers lay in opposition without any invasion. This has provided researchers opportunities to accurately tease out some of the mechanisms associated with maternal-fetal interface adaptations to the constantly evolving needs of a developing conceptus. Another unique feature of porcine pregnancy is the conceptus derived recruitment of immune cells during the window of conceptus attachment. These immune cells in turn participate in pregnancy associated vascular changes and contribute toward tolerance to the semi-allogeneic fetus. However, the precise mechanism of how maternal-fetal cells communicate during the critical times in gestation is not fully understood. Recently, it has been established that bi-directional communication between fetal trophoblasts and maternal cells/tissues is mediated by extracellular vesicles (EVs) including exosomes. These EVs are detected in a variety of tissues and body fluids and their role has been described in modulating several physiological and pathological processes including vascularization, immune-modulation, and homeostasis. Recent literature also suggests that these EVs (exosomes) carry cargo (nucleic acids, protein, and lipids) as unique signatures associated with some of the pregnancy associated pathologies. In this review, we provide overview of important mechanisms in porcine pregnancy success and failure and summarize current knowledge about the unique cargo containing biomolecules in EVs. We also discuss how EVs (including exosomes) transfer their contents into other cells and regulate important biological pathways critical for pregnancy success.

Carbon monoxide increases utero-placental angiogenesis without impacting pregnancy specific adaptations in mice

BACKGROUND

Cigarette smokers have a reduced risk of developing preeclampsia, possibly attributed to an increase in carbon monoxide (CO) levels. Carbon monoxide is a gasotransmitter that has been implicated in maintaining vascular tone, increasing angiogenesis, and reducing inflammation and apoptosis at physiological concentrations. Moderately increasing CO concentrations may have therapeutic potential to prevent or treat preeclampsia; however, the effects of CO on pregnancy are under studied. Our objective was to investigate the effect of CO on major angiogenic and inflammatory markers in pregnancy, and to evaluate the effect of CO on indicators of placental health.

FINDINGS

Pregnant CD-1 mice were constantly exposed to either ambient air or 250 ppm CO from conception until gestation day (GD)10.5 or GD16.5. Using a qRT-PCR array, we identified that CO increased expression of major angiogenic genes at the implantation site on GD10.5, but not GD16.5. Pro-inflammatory cytokines in the plasma and tissue lysates from implantation sites in treated mice were not significantly different compared to controls. Additionally, CO did not alter the implantation site phenotype, in terms of proliferative capacity, invasiveness of trophoblasts, or abundance of uterine natural killer cells.

CONCLUSIONS

This study suggests that CO exposure is pro-angiogenic at the maternal-fetal interface, and is not associated with demonstrable concerns during murine pregnancy. Future studies are required to validate safety and efficacy of CO as a potential therapeutic for vascular insufficiency diseases such as preeclampsia and intrauterine growth restriction.

Measurements of circulating progesterone and estrone sulfate concentrations as a diagnostic and prognostic tool in porcine pregnancy revisited

The main goal of this study was to examine the utility of measuring systemic concentrations of steroid hormones, namely progesterone (P₄) and estrone sulfate (E₁S), for monitoring the progression of porcine pregnancy and predicting sow fertility. There were 3 subsets of artificially inseminated (AI'd) sows used in the present experiments: (i) animals sacrificed on gestational day 20 (gd20; n = 16) or (ii) gd50 (n = 16; Experiment 1), and (iii) animals maintained throughout pregnancy (n = 24; Experiment 2). Blood samples (10 mL) were drawn from the orbital sinus and the endocrine data determined at different time points around ovulation/artificial insemination (gd0 (first AI), gd1 (second AI), and gd2) and maternal recognition of pregnancy (gd11), as well as on gd20 and gd50 (during 2 periods of increased embryonic/fetal mortality in swine) were examined for correlations with the numbers of healthy, arrested, and reabsorbing embryos (Experiment 1) or with the number of live, stillborn, and mummified piglets recorded at farrowing (Experiment 2). No correlations were recorded between circulating concentrations of both steroids and the numbers of healthy, arresting, or reabsorbing conceptuses on gd20 or 50 (Experiment 1). The number of corpora lutea (CL) was directly related to the number of healthy embryos/conceptuses on gd20 and 50 (r = 0.71, P = 0.007 and r = 0.76, P = 0.0007, respectively) and the number of arresting embryos on gd20 (r = 0.54, P = 0.05), and negatively correlated with the number of reabsorbing embryos on gd20 (r = -0.53, P = 0.05). In Experiment 2, circulating P₄ concentrations on gd11 related directly to the number of live-born piglets (r = 0.46, P < 0.04). Systemic E₁S concentrations on gd0, gd1, gd2 and gd50 were correlated with the number of mummified conceptuses recorded at farrowing (r = 0.50, P = 0.03; r = 0.59, P = 0.01; r = 0.48, P = 0.04; and r = 0.56, P = 0.01, respectively) and plasma concentrations of E₁S on gd20 related directly to the number of stillborn piglets (r = 0.60, P = 0.02). In summary, the number of CL on gd20 and 50 is a reliable marker of embryonic/fetal pig status. Measurements of P₄ and E₁S on gd20 and 50 showed limited diagnostic value (ie, were not indicative of the number of healthy and abnormally developing embryos/fetuses). However, measurements of circulating P₄ and E₁S concentrations during the periconceptional period and in the early/mid-pregnancy of sows have the makings of a practical method to predict gestational outcomes.

An epigenetic increase in mitochondrial fission by MiD49 and MiD51 regulates the cell cycle in cancer: Diagnostic and therapeutic implications

Excessive proliferation and apoptosis-resistance are hallmarks of cancer. Increased dynamin-related protein 1 (Drp1)-mediated mitochondrial fission is one of the mediators of this phenotype. Mitochondrial fission that accompanies the nuclear division is called mitotic fission and occurs when activated Drp1 binds partner proteins on the outer mitochondrial membrane. We examine the role of Drp1-binding partners, mitochondrial dynamics protein of 49 and 51 kDa (MiD49 and MiD51), as drivers of cell proliferation and apoptosis-resistance in non-small cell lung cancer (NSCLC) and invasive breast carcinoma (IBC). We also evaluate whether inhibiting MiDs can be therapeutically exploited to regress cancer. We show that MiD levels are pathologically elevated in NSCLC and IBC by an epigenetic mechanism (decreased microRNA-34a-3p expression). MiDs silencing causes cell cycle arrest through (a) increased expression of cell cycle inhibitors, p27^Kip1 and p21^Waf1 , (b) inhibition of Drp1, and (c) inhibition of the Akt-mTOR-p70S6K pathway. Silencing MiDs leads to mitochondrial fusion, cell cycle arrest, increased apoptosis, and tumor regression in a xenotransplant NSCLC model. There are positive correlations between MiD expression and tumor size and grade in breast cancer patients and inverse correlations with survival in NSCLC patients. The microRNA-34a-3p-MiDs axis is important to cancer pathogenesis and constitutes a new therapeutic target.

IL-17A Modulates Peritoneal Macrophage Recruitment and M2 Polarization in Endometriosis

Endometriosis is a debilitating gynecological disease characterized by the extrauterine presence of endometrial-like tissues located on the peritoneal membrane and organs of the pelvic cavity. Notably, dysfunctional immune activation in women with endometriosis could also contribute to the development of disease. In particular, alternatively activated (M2) peritoneal macrophages are shown to aid peritoneal lesion development by promoting remodeling of extracellular matrix and neovascularization of lesions. However, the stimuli responsible for polarizing M2 macrophages in endometriosis remain elusive. Interleukin-17A (IL-17A) can induce M2 macrophage polarization in other disease models and IL-17A is elevated in the plasma and endometriotic lesions of women with endometriosis. In this study, we investigated whether IL-17A could induce macrophage recruitment and M2 polarization, while promoting endometriotic lesion growth through enhanced vascularization. By utilizing a co-culture of macrophage-like THP-1 cells with an endometriotic epithelial cell line, our in vitro results suggest that IL-17A indirectly induces M2 markers CCL17 and CD206 by interacting with endometriotic epithelial cells. Further, in a syngeneic mouse model of endometriosis, IL-17A treatment increased macrophages in the peritoneum, which were also M2 in phenotype. However, IL-17A treatment did not augment proliferation or vascularization of the lesion in the study time frame. These findings suggest that IL-17A may be a stimulus inducing the pathogenic polarization of macrophages into the M2 phenotype by first acting on the endometriotic lesion itself.

Neutrophil recruitment and function in endometriosis patients and a syngeneic murine model

Endometriosis is a chronic inflammatory, gynecological disease characterized by the presence of endometrial-like tissue lesions outside of the uterus. Neutrophils are elevated in the systemic circulation and peritoneal fluid of endometriosis patients; however, whether and how neutrophils contribute to endometriosis pathophysiology remain poorly understood. With emerging roles for neutrophils in chronic and sterile inflammatory conditions, we sought to provide in-depth characterization of neutrophil involvement in endometriosis. We demonstrate that neutrophils reside within patient endometriotic lesions and that patient lesions possess a microenvironment that may influence neutrophil recruitment and function. We also provide the first evidence that systemic circulating neutrophils from endometriosis patients display distinct transcriptomic differences compared neutrophils from healthy control subjects. Time course characterization of our syngeneic, immunocompetent mouse model of endometriosis revealed that neutrophils are rapidly recruited to the peritoneal environment early after endometriotic lesion establishment and remain present in murine lesions long term. In vivo neutrophil depletion altered the systemic and peritoneal immune microenvironment of mice with endometriosis as demonstrated by changes in pro-inflammatory and angiogenic mediators. Taken together, these findings highlight a novel role for neutrophils in early events such as angiogenesis and modulation of the local inflammatory environment associated with endometriosis pathogenesis.

Extracellular vesicles from endometriosis patients are characterized by a unique miRNA-lncRNA signature

With multifactorial etiologies, combined with disease heterogeneity and a lack of suitable diagnostic markers and therapy, endometriosis remains a major reproductive health challenge. Extracellular vesicles (EVs) have emerged as major contributors of disease progression in several conditions, including a variety of cancers; however, their role in endometriosis pathophysiology has remained elusive. Using next-generation sequencing of EVs obtained from endometriosis patient tissues and plasma samples compared with controls, we have documented that patient EVs carry unique signatures of miRNAs and long noncoding RNAs (lncRNAs) reflecting their contribution to disease pathophysiology. Mass spectrophotometry-based proteomic analysis of EVs from patient plasma and peritoneal fluid further revealed enrichment of specific pathways, as well as altered immune and metabolic processes. Functional studies in endometriotic epithelial and endothelial cell lines using EVs from patient plasma and controls clearly indicate autocrine uptake and paracrine cell proliferative roles, suggestive of their involvement in endometriosis. Multiplex cytokine analysis of cell supernatants in response to patient and control plasma-derived EVs indicate robust signatures of important inflammatory and angiogenic cytokines known to be involved in disease progression. Collectively, these findings suggest that endometriosis-associated EVs carry unique cargo and contribute to disease pathophysiology by influencing inflammation, angiogenesis, and proliferation within the endometriotic lesion microenvironment.

Understanding the role of IL-33 in endometriosis associated inflammation and pathology

Introduction

Endometriosis (EM) is a chronic inflammatory disease categorized by the growth of endometrial tissue on the ovaries, peritoneal wall and other internal organs. Despite it’s prevalence (176 million women worldwide), the etiology is unknown. Currently, there is a significant knowledge gap regarding how the immune microenvironment contributes to the progression of EM (specifically inflammation, pain and fibrosis). We have shown that interleukin(IL)-33 is produced by EM lesions and drives pathology in a mouse model of EM. We are now investigating, mechanistically, how IL-33 contributes to EM and whether IL-33 neutralization could alleviate the pathology.

Methods

Female C57BL/6 mice were induced with EM and were treated with PBS (n=10) or IL-33 (n=10) every other day. After 2 weeks, the mice were euthanized and plasma, peritoneal fluid (PF) and EM lesions were collected. Cytokines in the plasma and PF were analyzed using a multiplex array. Immune cell populations in the PF were evaluated using CyTOF. Finally, sectioned lesions were stained for markers of innervation, proliferation and fibrosis. To establish cause and effect, mice were induced with EM and treated with IL-33+anti-IL-33 antibody (n=10) or IL-33+isotype control (n=10).

Results

Mice treated with IL-33 had elevated cytokines (e.g. IL-5) in the plasma and PF and EM lesions exhibited drastic changes in morphology. Additionally, both innate and adaptive immune cells were altered in the PF of IL- 33 treated mice. Neutralizing IL-33 reduced inflammation and immune cell recruitment.

Conclusions

Overall, these results show that IL-33 drives hallmark pathologies of endometriosis and neutralization of IL-33 could provide a novel therapeutic target for EM.

Effects of placental growth factor deficiency on behavior, neuroanatomy, and cerebrovasculature of mice

Preeclampsia, a hypertensive syndrome occurring in 3-5% of human pregnancies, has lifelong health consequences for fetuses. Cognitive ability throughout life is altered, and adult stroke risk is increased. One potential etiological factor for altered brain development is low concentrations of proangiogenic placental growth factor (PGF). Impaired PGF production may promote an antiangiogenic fetal environment during neural and cerebrovascular development. We previously reported delayed vascularization of the hindbrain, altered retinal vascular organization, and less connectivity in the circle of Willis in Pgf^-/- mice. We hypothesized Pgf^-/- mice would have impaired cognition and altered brain neuroanatomy in addition to compromised cerebrovasculature. Cognitive behavior was assessed in adult Pgf^-/- and Pgf^+/+ mice by four paradigms followed by postmortem high-resolution MRI of neuroanatomy. X-ray microcomputed tomography imaging investigated the three-dimensional cerebrovascular geometry in another cohort. Pgf^-/- mice exhibited poorer spatial memory, less depressive-like behavior, and superior recognition of novel objects. Significantly smaller volumes of 10 structures were detected in the Pgf^-/- compared with Pgf^+/+ brain. Pgf^-/- brain had more total blood vessel segments in the small-diameter range. Lack of PGF altered cognitive functions, brain neuroanatomy, and cerebrovasculature in mice. Pgf^-/- mice may be a preclinical model for the offspring effects of low-PGF preeclampsia gestation.

The Immunopathophysiology of Endometriosis

Endometriosis is a chronic, inflammatory, estrogen-dependent disease characterized by the growth of endometrial tissue outside of the uterine cavity. Although the etiology of endometriosis remains elusive, immunological dysfunction has been proposed as a critical facilitator of ectopic lesion growth following retrograde menstruation of endometrial debris. However, it is not clear whether this immune dysfunction is a cause or consequence of endometriosis. Thus, here we provide in-depth insights into our current understanding of the immunopathophysiology of endometriosis and highlight challenges and opportunities for future research. With the explosion of successful immune-based therapies targeting various chronic inflammatory conditions, it is crucial to determine whether immune dysfunction can be therapeutically targeted in endometriosis.

Developmental origins of pregnancy-induced cardiac changes: establishment of a novel model using the atrial natriuretic peptide gene-disrupted mice

Pregnancy evokes many challenges on the maternal cardiovascular system that may unmask predispositions for future disease. This is particularly evident for women who develop pregnancy-related disorders, for example, pre-eclampsia and gestational diabetes or hypertension. Such pregnancy-related syndromes increase the risk for cardiovascular disease (CVD) postpartum. As a result, pregnancy has been termed as a cardiovascular stress test and an indicator or marker to predict the development of CVD later in life. In addition, pregnancy-related disorders impact the development of offspring also placing them at a higher risk for disease. Utilizing pregnancy as a physiological stressor, the current investigation sought to determine whether the cardiovascular system of offspring exposed to gestational hypertension in utero would respond adversely to the stress of pregnancy. Heterozygous atrial natriuretic peptide gene-disrupted (ANP^+/-) offspring were generated by either crossing male wildtype ANP^+/+ with female knockout ANP^-/- to produce ANP^+/-KO mice or crossing female wildtype ANP^+/+ with male knockout ANP^-/- to produce ANP^+/-WT mice. To study the cardiovascular stress induced by pregnancy, female ANP^+/-WT and ANP^+/-KO mice were mated with male wildtype ANP^+/+ mice to initiate pregnancy. Cardiac size and molecular expression of the renin-angiotensin (RAS) and natriuretic peptide systems (NPS) were compared between offspring groups. Our data demonstrate that gestational hypertension and lack of maternal ANP did not significantly impact the progression and regression of pregnancy-induced cardiac hypertrophy over gestation and postpartum in ANP^+/- offspring. Additionally, the molecular cardiac expression of the RAS and NPS did not differ between offspring groups. Future investigation should assess potential differences in cardiac function and the impact of fetal-programming on offspring cardiovascular adaptations during pregnancy in more severe models of pregnancy-related hypertensive syndrome such as angiotensin II or isoproterenol infusion.

Implications of immune dysfunction on endometriosis associated infertility

Endometriosis is a complex, inflammatory disease that affects 6-10% of reproductive-aged women. Almost half of the women with endometriosis experience infertility. Despite the excessive prevalence, the pathogenesis of endometriosis and its associated infertility is unknown and a cure is not available. While many theories have been suggested to link endometriosis and infertility, a consensus among investigators has not emerged. In this extensive review of the literature as well as research from our laboratory, we provide potential insights into the role of immune dysfunction in endometriosis associated infertility. We discuss the implication of the peritoneal inflammatory microenvironment on various factors that contribute to infertility such as hormonal imbalance, oxidative stress and how these could further lead to poor oocyte, sperm and embryo quality, impaired receptivity of the endometrium and implantation failure.

Interleukin-33 modulates inflammation in endometriosis

Endometriosis is a debilitating condition that is categorized by the abnormal growth of endometrial tissue outside the uterus. Although the pathogenesis of this disease remains unknown, it is well established that endometriosis patients exhibit immune dysfunction. Interleukin (IL)-33 is a danger signal that is a critical regulator of chronic inflammation. Although plasma and peritoneal fluid levels of IL-33 have been associated with deep infiltrating endometriosis, its contribution to the disease pathophysiology is unknown. We investigated the role of IL-33 in the pathology of endometriosis using patient samples, cell lines and a syngeneic mouse model. We found that endometriotic lesions produce significantly higher levels of IL-33 compared to the endometrium of healthy, fertile controls. In vitro stimulation of endometrial epithelial, endothelial and endometriotic epithelial cells with IL-33 led to the production of pro-inflammatory and angiogenic cytokines. In a syngeneic mouse model of endometriosis, IL-33 injections caused systemic inflammation, which manifested as an increase in plasma pro-inflammatory cytokines compared to control mice. Furthermore, endometriotic lesions from IL-33 treated mice were highly vascularized and exhibited increased proliferation. Collectively, we provide convincing evidence that IL-33 perpetuates inflammation, angiogenesis and lesion proliferation, which are critical events in the lesion survival and progression of endometriosis.

Maternal Circulating microRNAs and Pre-Eclampsia: Challenges for Diagnostic Potential

Pre-eclampsia (PE) is a common hypertensive disorder of pregnancy with a significant impact on maternal and neonatal mortality and morbidity. While the pathogenesis of PE has been well described, identification of a biomarker(s) with robust predictive utility in identifying women at the highest risk of developing the condition has yet to be identified. In the search for diagnostic markers, those that may be obtained from the circulation are preferred alternatives to those derived from organ tissue samples. Because of their stability in plasma, microRNAs (miRNAs) have been explored as biomarkers in a host of disease states, although there is comparably little literature available on the circulating miRNAome of PE. This article provides a narrative review on the current state of knowledge on miRNAs associated with PE. Literature on circulating miRNAs is presented and the challenges to developing the diagnostic and prognostic utility of miRNAs in this context is discussed.

Cervical cerclage placement decreases local levels of proinflammatory cytokines in patients with cervical insufficiency

BACKGROUND

Cervical insufficiency is characterized by premature, progressive dilation and shortening of the cervix during pregnancy. If left unattended, this can lead to the prolapse and rupture of the amniotic membrane, which usually results in midtrimester pregnancy loss or preterm birth. Previous studies have shown that proinflammatory cytokines such as interleukin-1β, interleukin-6, interleukin-8, and tumor necrosis factor alpha are up-regulated in normal parturition but are also associated with preterm birth. Studies evaluating such markers in patients with cervical insufficiency have evaluated only their diagnostic potential. Even fewer studies have studied them within the context of cerclage surgery.

OBJECTIVES(S)

The objective of the study was to evaluate the impact of local and systemic inflammatory markers on the pathogenesis of cervical insufficiency and the effect of cerclage surgery on the local immune microenvironment of women with cervical insufficiency.

STUDY DESIGN

We recruited 28 pregnant women (12-20 weeks' gestation) diagnosed with insufficiency and referred for cerclage surgery and 19 gestational age-matched normal pregnant women as controls. Serum and cervicovaginal fluid samples were collected before and after cerclage surgery and during a routine checkup for normal women and analyzed using a targeted 13-plex proinflammatory cytokine assay.

RESULTS

Before surgery, patients with cervical insufficiency had higher levels of interleukin-1β, interleukin-6, interleukin-12, monocyte chemoattractant protein-1 and tumor necrosis factor alpha in cervicovaginal fluid compared to controls, but after surgery, these differences disappeared. No differences were found in serum of insufficiency versus control women. In patients with insufficiency, the levels of interleukin-1β, interleukin-6, interleukin-8, monocyte chemoattractant protein-1, and interferon gamma in cervicovaginal fluid declined significantly after cerclage compared with before intervention, but these changes were not detected in serum.

CONCLUSION

Compared with normal women, patients with cervical insufficiency have elevated levels of proinflammatory cytokines in cervicovaginal fluid but not in serum, suggesting a dysregulation of the local immune environment. Cerclage intervention led to a significant decline in these proinflammatory cytokines, suggesting that cerclage may help reduce local inflammation in cervical insufficiency.

KRAS Activation and over-expression of SIRT1/BCL6 Contributes to the Pathogenesis of Endometriosis and Progesterone Resistance

Endometriosis is an inflammatory condition that is associated with progesterone resistance and cell proliferation, resulting in pain, infertility and pregnancy loss. We previously demonstrated phosphorylation of STAT3 in eutopic endometrium of infertile women with this disorder leading to over-expression of the oncogene BCL6 and stabilization of hypoxia-induced factor 1 alpha (HIF-1α). Here we report coordinated activation of KRAS and over-expression of Sirtuin 1 (SIRT1), a histone deacetylase and gene silencer, in the eutopic endometrium from women with endometriosis throughout the menstrual cycle. The mice with conditional activation of KRAS in the PGR positive cells reveal an increase of SIRT1 expression in the endometrium compared to control mice. The expression of progesterone receptor target genes including the Indian Hedgehog pathway genes are significantly down-regulated in the mutant mice. SIRT1 co-localizes with BCL6 in the nuclei of affected individuals and both proteins bind to and suppress the promoter of GLI1, a critical mediator of progesterone action in the Indian Hedgehog pathway, by ChIP analysis. In eutopic endometrium, GLI1 expression is reduced in women with endometriosis. Together, these data suggest that KRAS, SIRT1 and BCL6 are coordinately over-expressed in eutopic endometrium of women with endometriosis and likely participate in the pathogenesis of endometriosis.

Influences of placental growth factor on mouse retinal vascular development

BACKGROUND

Placental growth factor (PGF) is important for wound-healing and vascular collaterogenesis. PGF deficiency is associated with preeclampsia, a hypertensive disease of human pregnancy. Offspring born to preeclamptic mothers display cognitive impairments and brain vascular and neurostructural deviations. Low PGF production during development may contribute to alterations in offspring cerebrovascular beds. Retina is a readily accessible part of the central nervous system with a well-described pattern of vascular development in mice. Impacts of PGF deficiency were addressed during mouse retinal vascularization.

RESULTS

Retinal vessels were compared between Pgf^-/- and congenic C57BL/6 (B6) mice. PGF deficiency altered neonatal retinal vascularization patterns. Some anatomic alterations persisted into adulthood, particularly in males. Greater arterial wall collagen IV expression was found in adult Pgf^-/- females. Pregnancy (studied in adult females at gestational days 11.5 or 18.5) induced subtle changes upon the mother's retinal vasculature but these pregnancy-induced changes did not differ between genotypes. Significant sex-related differences occurred between adult male and female B6 although sexually dimorphic retinal vascular differences were absent in B6 neonates.

CONCLUSIONS

Overall, PGF has a role in retinal vascular angiogenesis and vessel organization during development but does not affect retinal vessel adaptations in adult females during pregnancy. Developmental Dynamics 246:700-712, 2017. © 2017 Wiley Periodicals, Inc.

A balancing act: RNA binding protein HuR/TTP axis in endometriosis patients

Endometriosis, a major reproductive pathology affecting 8-10% of women is characterized by chronic inflammation and immune dysfunction. Human antigen R (HuR) and Tristetraprolin (TTP) are RNA binding proteins that competitively bind to cytokines involved in inflammation including: tumor necrosis factor alpha (TNF-α), granulocyte macrophage colony stimulating factor (GM-CSF), interleukin 6 (IL-6) among others, and stabilize and destabilize them, respectively. The aim of this study was to examine RNA binding protein (RNABP) HuR/TTP axis in endometriosis patients compared to menstrual stage matched healthy fertile controls in hopes of better understanding their contribution to the pathogenesis of endometriosis. Additionally, using a targeted in vitro siRNA approach, we examined whether knock-down of TTP can play a functional role on other RNABPs that competitively bind to inflammatory targets of TTP in both endometriotic and endometrial epithelial cell lines. Our results suggest that RNABPs TTP and HuR are dysregulated in endometriotic lesions compared to matched eutopic patient samples as well endometrium from healthy controls. Silencing of TTP in endometriotic and endometrial epithelial cells revealed differential response to inflammatory cytokines and other RNABPs. Our results suggest potential involvement of HuR/TTP RNA binding protein axis in regulation of inflammation in endometriosis.

Pregnancy and spontaneous fetal loss: A pig perspective

Pigs have a unique, non-invasive epitheliochorial placenta where maternal and fetal layers lay in apposition. Indentation of fetal capillaries into the trophoblasts and maternal capillaries into the uterine epithelium reduce the distance between the fetal and maternal blood, ensuring nutrient transfer for proper conceptus development. Another unique feature of pig pregnancy is conceptus-mediated immune cell enrichment during the early stages of conceptus attachment (around gestation Day 15). This period coincides with the development of vasculature networks at the maternal-fetal interface, which is critical for successful conceptus growth. Specific chemokines, their receptors, and chemokine decoy receptor networks coordinate this immune cell enrichment and the positioning at the maternal-fetal interface. The recruited immune cells, in turn, adopt a specialized phenotype to support key processes of maternal-fetal adaptations, including tolerance to the semi-allogeneic fetus and supporting vascularization. Disturbance in coordinated cross talk between the conceptus and maternal endometrium is an important mechanism associated with spontaneous fetal loss. The exact mechanism of fetal loss is still not yet identified, although research in the last two decades point to various factors including genetics, nutrition, uterine capacity, placental efficiency, and imbalanced immune factors at the maternal-fetal interface. In this review, we summarize some of the recent advances in endometrial immune cell functions and their regulation. We also provide insights into endometrial/placental transcriptome, microRNA biology, and extravesicular transport across the maternal-fetal interface, as well as their potential implications in porcine pregnancy success or failure.

RNA-Binding Proteins in Female Reproductive Pathologies

RNA-binding proteins are key regulatory molecules involved primarily in post-transcriptional gene regulation of RNAs. Post-transcriptional gene regulation is critical for adequate cellular growth and survival. Recent reports have shown key interactions between these RNA-binding proteins and other regulatory elements, such as miRNAs and long noncoding RNAs, either enhancing or diminishing their response to RNA stabilization. Many RNA-binding proteins have been reported to play a functional role in mediation of cytokines involved in inflammation and immune dysfunction, and some have been classified as global post-transcriptional regulators of inflammation. The ubiquitous expression of RNA-binding proteins in a wide variety of cell types and their unique mechanisms of degradative action provide evidence that they are involved in reproductive tract pathologies. Aberrant inflammation and immune dysfunction are major contributors to the pathogenesis and disease pathophysiology of many reproductive pathologies, including ovarian and endometrial cancers in the female reproductive tract. Herein, we discuss various RNA-binding proteins and their unique contributions to female reproductive pathologies with a focus on those mediated by aberrant inflammation and immune dysfunction.

Chronic effects of an anti-angiogenic thrombospondin-1 mimetic peptide, ABT-898, on female mouse reproductive outcomes

BACKGROUND

Angiogenesis is an essential process in endometriosis disease progression. Earlier, we demonstrated that anti-angiogenic peptide, ABT-898 prevents neoangiogenesis of human endometriotic lesions in a xenograft mouse model. Since angiogenesis is essential for normal ovarian and uterine function, we evaluated effects of ABT-898 on normal female reproductive processes in mice.

METHODS

Cycling female C57BL/6N mice were dosed with ABT-898 (100 mg/kg) or 5 % dextrose control for 21 consecutive days to cover multiple estrous cycles (average estrous cycle 4 to 5 days in mice). Pregnant female mice were dosed with ABT-898 (100 mg/kg) or control on alternate days over the course of gestation, beginning at gestation day 7.5 to 17.5 (gestation length 21 days). Histological analysis along with CD31 and Vimentin immunohistochemistry were performed on ovaries and uteri obtained from treated and control mice. To understand the influence of ABT-898 on systemic angiogenic factors, a Pro Mouse Cytokine 9-plex assay was performed on plasma samples obtained from mice prior to treatment, during the second week of ABAT-898 or control treatment and on the last day of treatment.

RESULTS

ABT-898 did not affect the number of estrous cycles over the 21 day treatment compared to control. Histological analysis of ovaries found no difference in the number of primordial, primary, secondary, and antral follicles between ABT-898 treated and control groups. Similarly, no difference was observed in the microvessel density between ABT-898 treated and control uteri, ovarian follicles or corpus luteum when assessed using CD31 or vimentin immunohistochemistry. Electron microscopy revealed similar capillary structure and appearance in both ABT-898 treated and control uteri. Although peripheral blood angiogenic cytokine profiles (IL-15, IL-18, M-CSF, b-FGF, PDGF-bb, MIG, MIP-2, LIF and VEGF) changed over the course of the intervention, there was no significant difference between ABT-898 and control groups at any of the studied time points. Treatment with ABT-898 during pregnancy had no effect on litter size at birth, pup weight at birth or pup weight at weaning.

CONCLUSION

Our findings suggest that ABT-898 may not alter angiogenesis dependent reproductive processes in female mice. However, an extensive reproductive toxicology screening is required to substantiate use of ABT-898 in future.

Altered expression of chemokines and their receptors at porcine maternal-fetal interface during early and mid-gestational fetal loss

Chemokines play a significant role in pregnancy, especially during embryonic attachment and placental development. During early pregnancy, immune cells are recruited extensively to the endometrium in several species including pigs. However, this recruitment is solely mediated by the presence of the conceptus in pigs making it a unique feature compared with other species (humans, primates and mice). To understand the biological significance of chemokine expression and immune cell recruitment in the context of fetal loss, we investigate a well-characterized porcine fetal loss model during the window of early pregnancy at gestational day (gd) 20 and mid-pregnancy (gd50). These periods coincide with 25-40 % of conceptus loss. Using targeted quantitative polymerase chain reaction and Western blot approaches, we screened a specific set of chemokines. Comparisons were made with endometrial lymphocytes (ENDO LY), endometrium and chorioallantoic membranes (CAM) associated with spontaneously arresting and healthy conceptus attachment sites (CAS). mRNA expression studies revealed an increased expression of CXCR3 and CCR5 in ENDO LY and of CXCL10, CXCR3, CCL5 and CCR5 in the endometrium associated with arresting CAS at gd20. DARC was decreased in the endometrium at gd50. CCL1 was increased in CAM associated with arresting CAS at gd50. Some of these differences were also noted at the protein level (CXCL10, CXCR3, CCL5 and CCR5) in the endometrium and CAM. CD45+ immunohistochemistry demonstrated a significantly higher localization in ENDO LY in the endometrium associated with healthy versus arresting counterparts. Most of these differences were observed in early pregnancy and might contribute towards a shift in immune cell functions.

Immune-inflammation gene signatures in endometriosis patients

OBJECTIVE

To determine if the molecular profiles of endometriotic lesions contain informative measures of inflammation and immune dysfunction that may contribute to better understanding of the interplay between immune dysfunction and inflammation and their contribution to endometriosis pathogenesis.

DESIGN

Immune and inflammation transcriptomic analysis with the use of the Nanostring nCounter GX Human Immunology V2 platform (579 human immune and inflammation-related genes and 15 housekeeping genes).

SETTING

Academic university and teaching hospital.

INTERVENTION(S)

None.

PATIENT(S)

Stage III-IV endometriosis patients with infertility (n = 8) and fertile disease-free control women undergoing tubal ligation (n = 8). Menstrual stage was matched to secretory phase in all participants.

MAIN OUTCOME MEASURE(S)

Immune and inflammation transcriptomics quantification from ectopic endometriotic lesions and matched eutopic endometrium from patients. Endometria of fertile women served as control subjects.

RESULT(S)

Our results displayed endometriotic lesions as molecularly distinct entities compared with eutopic endometrium and endometrium of control samples; 396 out of 579 screened immune and inflammation-related genes were significantly different in ectopic tissues compared with control endometrium. Most importantly, eutopic endometrium of the patients displayed a unique molecular profile compared with the control endometrium (91/579 genes were significantly different), particularly of genes involved in regulation of cell apoptosis and decidualization.

CONCLUSION(S)

We characterize differential expression of immune-inflammation genes in endometriosis patients, and show molecular distinction of eutopic endometrium of patients compared with control fertile women.

Protein Inhibitor of Activated STAT3 (PIAS3) Is Down-Regulated in Eutopic Endometrium of Women with Endometriosis

Endometriosis is a major cause of chronic pelvic pain and infertility. Activation of STAT3 appears central to the inflammatory phenotype of eutopic endometrium in women with endometriosis. However, the molecular mechanism by which this occurs remains unknown. Our objective is to determine how STAT3 activity is regulated in endometriosis. Protein inhibitor of activated STAT3 (PIAS3) is a negative regulator of STAT3 activity. We examined the levels of PIAS3 in endometrium from women with and without endometriosis using Western blot analysis and immunohistochemistry. Levels of PIAS3 are significantly lower, in contrast with phosphorylation of STAT3, in women with endometriosis compared to women without endometriosis. Furthermore, induction of endometriosis in the baboon showed a significant reduction of PIAS3 expression during the progression of the disease. Interferon-γ (INFγ) reduces PIAS3 protein levels and increases phospho-STAT3 levels through CXCL10 in endometrial cells, Ishikawa, and 12Z cells. These results suggest that attenuation of PIAS3 causes aberrant activation of STAT3 in endometriosis, leading to inflammatory changes that may impair fertility or cause pain.

Moderate Exercise Attenuates Lipopolysaccharide-Induced Inflammation and Associated Maternal and Fetal Morbidities in Pregnant Rats

Fetal growth restriction (FGR) and coagulopathies are often associated with aberrant maternal inflammation. Moderate-intensity exercise during pregnancy has been shown to increase utero-placental blood flow and to enhance fetal nutrition as well as fetal and placental growth. Furthermore, exercise is known to reduce inflammation. To evaluate the effect of moderate-intensity exercise on inflammation associated with the development of maternal coagulopathies and FGR, Wistar rats were subjected to an exercise regime before and during pregnancy. To model inflammation-induced FGR, pregnant rats were administered daily intraperitoneal injections of E. coli lipopolysaccharide (LPS) on gestational days (GD) 13.5–16.5 and sacrificed at GD 17.5. Control rats were injected with saline. Maternal hemostasis was assessed by thromboelastography. Moderate-intensity exercise prevented LPS-mediated increases in white blood cell counts measured on GD 17.5 and improved maternal hemostasis profiles. Importantly, our data reveal that exercise prevented LPS-induced FGR. Moderate-intensity exercise initiated before and maintained during pregnancy may decrease the severity of maternal and perinatal complications associated with abnormal maternal inflammation.

Evidence of inflammation and predisposition toward metabolic syndrome after pre-eclampsia

BACKGROUND

Pre-eclampsia (PE) is a hypertensive disorder of pregnancy characterized by exaggerated inflammatory and metabolic responses. Women with a history of PE are at increased risk of the metabolic syndrome (MetS) and cardiovascular disease although the pathophysiological underpinnings of this association remain unclear. This study aimed to compare levels of plasma immunoregulatory factors with the presence of cardiovascular and MetS risk factors in women with and without a history of PE.

STUDY DESIGN

Maternal plasma and general health survey data were collected from women 5 to 7months postpartum of uncomplicated pregnancies (n=28) and pregnancies complicated by PE (n=35). Maternal plasma samples were analyzed for 14 immunoregulatory factors using a high-sensitivity cytokine profiling array. Cardiovascular risk profiles were compiled on each participant for comparison against cytokine data.

RESULTS

Women with a history of PE exhibited increased blood pressure and plasma triglyceride levels compared to controls, although similar for parameters of obesity, fasting cholesterols, and glucose. While plasma levels of immunoregulatory cytokines were similar between control and PE subjects, PE subjects exhibited unique patterns of correlation between biophysical parameters and plasma cytokines. In particular, plasma IL-23, MIP-1α, IL-1β and IFN-γ levels were significantly correlated with parameters considered for MetS diagnosis in women without clinical evidence of the syndrome.

CONCLUSIONS

We report unique associations between pro-inflammatory markers and MetS criteria within a year following PE. Subclinical inflammation in women with a history of PE who are otherwise healthy may indicate a sensitization of these women toward metabolic disturbances, in particular MetS.

Differential expression of plasma microRNA in preeclamptic patients at delivery and 1 year postpartum

OBJECTIVE

Preeclampsia (PE) is a hypertensive disorder of pregnancy characterized by widespread maternal endothelial dysfunction. Although clinical signs subside following delivery, long-term risks associated with PE include hypertension, stroke, and cardiovascular disease. MicroRNAs (miRNAs) are emerging as critical regulators of biological function, and while alterations to the miRNAome have been described in the context of pregnancy and PE, the postpartum implications of PE on miRNA expression is unknown. The goal of this study was to characterize circulating miRNA profiles at the time of delivery and at 1 year postpartum for women who did and did not develop PE.

STUDY DESIGN

Using a targeted reverse transcription polymerase chain reaction approach, selected miRNAs putatively involved in the pathophysiology of PE were examined in 17 normotensive control and 13 PE maternal plasma samples at the time of delivery and 1 year postpartum. Ingenuity Pathway Analysis was used to map putative messenger RNA targets of differentially expressed miRNA to global molecular networks based on gene function.

RESULTS

Significant increases (P < .05) in 7 miRNAs with antiangiogenic, inflammatory, and apoptotic functions (miR-98-5p, miR-222-3p, miR-210-3p, miR-155-5p, miR-296-3p, miR-181a-5p, miR-29b-3p) were evident in maternal plasma at the time of severe PE compared to time-matched controls. Plasma samples from individuals who developed mild PE exhibited no changes compared to control samples for the subset of miRNAs analyzed here. Differential expression of plasma miRNA at the time of delivery for women with PE were largely resolved at 1 year postpartum, and reduced expression of only miR-221-3p (P < .05) was evident. Network analysis of putative targets of differentially regulated miRNA identified 11 interacting networks with enrichment for proteins involved in cardiovascular disease, organ system development and function, and cell signaling and interaction.

CONCLUSION

The systemic effect of PE on maternal systems is evident in the circulating miRNAome with substantial alterations in miRNA expression in women who develop severe PE. In addition we provide novel evidence of disruption to miR-221 expression 1 year postpartum following a pregnancy complicated by PE compared to normotensive time-matched controls, which may allude to persistent inflammation in these women after delivery.

IL-17A Contributes to the Pathogenesis of Endometriosis by Triggering Proinflammatory Cytokines and Angiogenic Growth Factors

Endometriosis is a chronic, inflammatory disease characterized by the growth of endometrial tissue in aberrant locations outside the uterus. Neoangiogenesis or establishment of new blood supply is one of the fundamental requirements of endometriotic lesion survival in the peritoneal cavity. IL-17A is emerging as a potent angiogenic and proinflammatory cytokine involved in the pathophysiology of several chronic inflammatory diseases such as rheumatoid arthritis and psoriasis. However, sparse information is available in the context of endometriosis. In this study, we demonstrate the potential importance of IL-17A in the pathogenesis and pathophysiology of endometriosis. The data show a differential expression of IL-17A in human ectopic endometriotic lesions and matched eutopic endometrium from women with endometriosis. Importantly, surgical removal of lesions resulted in significantly reduced plasma IL-17A concentrations. Immunohistochemistry revealed localization of IL-17A primarily in the stroma of matched ectopic and eutopic tissue samples. In vitro stimulation of endometrial epithelial carcinoma cells, Ishikawa cells, and HUVECs with IL-17A revealed significant increase in angiogenic (vascular endothelial growth factor and IL-8), proinflammatory (IL-6 and IL-1β), and chemotactic cytokines (G-CSF, CXCL12, CXCL1, and CX3CL1). Furthermore, IL-17A promoted tubulogenesis of HUVECs plated on Matrigel in a dose-dependent manner. Thus, we provide the first evidence, to our knowledge, that endometriotic lesions produce IL-17A and that the removal of the lesion via laparoscopic surgery leads to the significant reduction in the systemic levels of IL-17A. Taken together, our data show a likely important role of IL-17A in promoting angiogenesis and proinflammatory environment in the peritoneal cavity for the establishment and maintenance of endometriosis lesions.

Laser capture microdissection for gene expression analysis

Laser capture microdissection (LCM) is an excellent and perhaps the only platform to isolate homogeneous cell populations from specific microscopic regions of heterogeneous tissue section, under direct microscopic visualization. The basic operations of the LCM system are based on (a) microscopic visualization of phenotypically identified cells of interest, (b) selective adherence of cells to a melting thermolabile film/membrane using a low-energy infrared laser (IR system) or photovolatization of cells within a selected region (UV system), (c) capturing or catapulting of structurally intact cells from a stained tissue section. RNA/DNA or protein can be extracted from the cell or tissue fragments for downstream applications to quantitatively study gene expression. This method can be applied to many downstream analyses including but not limited to quantitative real-time polymerase chain reaction (PCR), microarray, DNA genotyping, RNA transcript profiling, generation of cDNA library, mass spectrometry analysis, and proteomic discovery.The application of LCM is described here to specifically and reliably obtain a homogeneous cell population in order to extract RNA to study microRNA expression by quantitative real-time PCR.

Compatibility of a novel thrombospondin-1 analog with fertility and pregnancy in a xenograft mouse model of endometriosis

Endometriosis is a gynecological disease defined by the growth of endometrium outside of the uterus. Although endometriosis contributes to 50% of female infertility cases, medical treatments are incompatible with pregnancy. Angiogenesis, the growth of blood vessels from existing vasculature, plays a crucial role in endometriotic lesion growth and survival. Previously, we demonstrated the effectiveness of thrombospondin-1 analog, ABT-898 (Abbott Laboratories) to inhibit endometriotic lesion vascularization in mice. We have now evaluated the trans-generational implications of ABT-898 treatment before and during mouse pregnancy. We hypothesized that ABT-898 would target lesion vasculature without affecting pregnancy, offspring development, or ovarian and uterine vascularity in mice. Endometriosis was induced using human endometrium in β-estradiol-primed BALB/c-Rag-2-/-Il2rγ-/- mice receiving intraperitoneal injections of ABT-898 (25 mg/kg) or 5% dextrose control for 21 days. Ultrasound assessment of lesion vascularization revealed a reduction in blood flow supplying treated lesions. Excised ABT-898 treated lesions stained for CD31+ endothelial cells exhibited a decrease in microvessel density. Following confirmation of estrous cycling, mice were bred and treated with ABT-898 on gestation days 7, 9, 11, 13, 15, 17, and 19. ABT-898 did not affect estrous cycling or pregnancy parameters including litter size across generations and offspring weight gain. Quantification of angiogenic cytokine plasma levels revealed no significant differences between treatment groups. Vimentin staining of the uterus and ovary revealed no observable effects of ABT-898. Similarly, no obvious histological anomalies were observed in the kidney, liver, ovary, or uterus following ABT-898 treatment. These results suggest that ABT-898 effectively inhibit endometriotic lesion vascularization without affecting trans-generational pregnancy outcomes in mice.

mRNA destabilizing factors: tristetraprolin expression at the porcine maternal-fetal interface

PROBLEM

To evaluate the expression of the tristetraprolin family and their selected targets during porcine pregnancy.

METHOD OF STUDY

Using qPCR and Western blot, mRNA and protein levels were compared between endometrium and chorioallantoic membrane (CAM) associated with healthy and impaired conceptuses at gestation day (gd) 20 and gd50, respectively. Immunohistochemistry was performed to determine localization of TIS11 family members at gd20 and 50.

RESULTS

Multiple significant differences (P < 0.05) in TIS11 family transcripts were observed in the aforementioned comparisons. GM-CSF was significantly higher in healthy endometrium and CAM from impaired conceptus attachment sites. TNF-α was elevated in CAM as compared to endometrium at gd50, regardless of conceptus health status. Immunohistochemical staining shows TIS11 family expressed in the glandular and luminal epithelium, as well as stromal cells in the uterus.

CONCLUSIONS

The shift in the expression of tristetraprolin (TTP) and TIS11D points to a potential role of these genes in regulating spontaneous fetal loss.

Expression of leptin and its long form receptor at the porcine maternal-fetal interface: contrasting healthy and arresting conceptus attachment sites during early and mid-pregnancy

BACKGROUND

It is well established that spontaneous conceptus loss in swine is associated with an imbalance of both angiogenic and immunological factors. Leptin (LEP), a metabolic hormone, has also been implicated in the promotion of angiogenesis. In this study, LEP and its long form receptor (OB-Rb) were evaluated during porcine pregnancy to assess their basal level of expression and their potential role in conceptus development.

METHODS

Expression and secretion of LEP and OB-Rb were quantified in the endometrium of non-pregnant (n = 5), and in the endometrium and chorioallantoic membrane (CAM) of pregnant sows (parity 2 to 5) at gestational days (gd) 20 (n = 8) and 50 (n = 8). Data were analyzed by a 3-way ANOVA testing the effects of conceptus health, tissue type and gestational day.

RESULTS

Leptin and OB-Rb transcripts were significantly higher (P < 0.05) in pregnant than in non-pregnant sows. Significantly greater LEP (P < 0.001) was detected in the endometrial tissue at gd20 compared with gd50. At the protein level, the lowest LEP expression (P < 0.01) was detected in the CAM at gd50, while OB-Rb protein was significantly lower (P < 0.01) at gd50 in the CAM than in the endometrium collected from gd20 and gd50 conceptus attachment sites. Immunofluorescence staining confirmed the expression of these proteins at both gestational days and in both tissue types.

CONCLUSIONS

Changes in the expression patterns of LEP and OB-Rb between gd20 and gd50 suggest a role for the LEP/OB-R complex at the early stages of porcine pregnancy, possibly affecting the attachment process. Further mechanistic studies are warranted to understand the specific role of leptin in porcine pregnancy.

A peptide inhibitor of synuclein-γ reduces neovascularization of human endometriotic lesions

Endometriosis is a chronic painful gynecological condition characterized by adherence and growth of endometrium outside of the uterine cavity. Neovascularization is essential to the developing endometriosis lesion to support its growth. Synuclein-γ (SNCG), a protein implicated in cellular proliferation, is associated with a broad range of malignancies as well as endometriosis. We hypothesized that SNCG plays an important role in the neovascularization and growth of endometriosis and blocking of SNCG will interfere with survival of endometriotic lesions in a mouse model. We developed SP012, a novel 12 amino acid peptide inhibitor of SNCG. SP012 inhibited three-dimensional endothelial cell tube formation in a dose-dependent manner. Using intravital microscopy, SP012 was shown to be successfully delivered to human endometriotic lesions in a xenograft mouse model in vivo. Alymphoid (BALB/c-Rag2-/-Il2rγ-/- lacking T, B and NK cells) mice were surgically induced with human endometriotic lesions and treated with SP012 or phosphate-buffered saline control. SP012 treated endometriotic lesions had decreased growth, development and vascularization at the time of necroscopy. Endometriotic lesions treated with SP012 also had fewer isolectin (+) microvessels. These results, using a mouse model, indicate that SNCG plays a role in the neovascularization and subsequent growth of human endometriotic lesions. Targeting SNCG function using peptide inhibitor might provide a potential therapeutic option for the treatment of endometriosis in the future.

MicroRNAs, immune cells and pregnancy

MicroRNAs (miRNAs) are a recently discovered class of non-coding RNAs that are expressed in many cell types, where they regulate the expression of complementary RNAs, thus modulating the stability and translation of mRNAs. miRNAs are predicted to regulate the expression of ∼50% of all protein coding genes in mammals. Therefore, they participate in virtually all cellular processes investigated so far. Altered miRNAs expressions are associated with both physiological (pregnancy) and pathological processes (cancer). As the dynamic maternal-fetal interface plays a critical role in the maintenance of successful pregnancy, it is not surprising that the miRNAs that are unique to reproductive tissues are abundantly expressed. Research in this field has demonstrated the presence and dysregulation of a distinct set of pregnancy-associated miRNAs; however, most studies have centered on localizing various miRNAs in reproductive microdomains associated with normal or complicated pregnancies. Although several independent miRNA regulatory mechanisms associated with endometrial receptivity, immune cells, angiogenesis and placental development have been studied, miRNA-mediated regulation of pregnancy remains poorly understood. This review provides a summary of the current data on miRNA regulation as well as functional profiles of miRNAs that are found in the uterus, in immune cells associated with maternal tolerance to the fetus, and those involved in angiogenesis and placental development.

The microRNAome of pregnancy: deciphering miRNA networks at the maternal-fetal interface

MicroRNAs (miRNAs) post-transcriptionally regulate a vast network of genes by inhibiting mRNA translation. Aberrant miRNA expression profiles have been implicated in pathologies and physiological processes including pregnancy and angiogenesis. Using our established model of implantation failure and spontaneous fetal loss in pigs (Sus scrofa), 236 miRNAs were profiled and compared between 1) non-pregnant and pregnant endometrium, 2) maternal and fetal tissues, and 3) viable and growth-arrested conceptus attachment sites by microarray and Real-Time PCR. Many significant differences in miRNA expression were observed between each of the aforementioned comparisons, and several were validated by PCR. Results indicated which miRNAs were important during pregnancy, which were elevated on the maternal or fetal side of the maternal-fetal interface, and they implicated the maternal expression of miR-10a, 27a, 29c, 323, 331-5p, 339-3p, 374b-5p, and 935 in the spontaneous loss observed in pigs. Several putative mRNA targets of the miRNAs (elevated in endometrium associated with arresting conceptuses) were assessed by quantitative Real-Time PCR and were depressed, supporting their regulation by miRNAs. Finally, targets were clustered by function to obtain ranked lists of gene networks that indicated which pathways/physiological processes might be important in non-pregnant (extracellular matrix factors) versus pregnant endometrium (nuclear transcription factor regulation), maternal (blood vessel development) versus fetal (neuronal differentiation) tissue, and healthy (extracellular matrix factors) versus arresting (GRAM domain) conceptus attachment sites. Overall, we demonstrate the presence of miRNAs on both sides of the maternal-fetal interface, implicate them in spontaneous fetal loss, and present a unique glimpse into the vast microRNAome of pregnancy.

Animal models for anti-angiogenic therapy in endometriosis

Endometriosis is a gynecological disease characterized by the growth of endometrium outside of the uterine cavity. It is often associated with dysmenorrhea, dyspareunia, pelvic pain and infertility. One of the key requirements for endometriotic lesions to survive is development of a blood supply to support their growth. Indeed, dense vascularization is characteristic feature of endometriotic lesions. This has led to the idea that suppression of blood vessel growth (anti-angiogenic therapy) may be a successful therapeutic approach for endometriosis. Potential effectiveness of anti-angiogenic therapies has been assessed in some animal models but there are no reports of human clinical trials. Without understanding the specific mechanism by which endometriosis lesions establish a new blood supply, short-term animal experiments will have limited value for translation into human medicine. Further, it is crucial to use appropriate animal models to assess efficacy of anti-angiogenic compounds. Syngeneic and autologous rodent models, where endometrial fragments are auto-transplanted into the peritoneal cavity are commonly used in anti-angiogenic therapy studies. Another approach is xenograft models where human endometrium is engrafted into immunodeficient mice. Here we review the animal models and experimental techniques used to evaluate anti-angiogenic therapies for endometriosis. We also review our own work on the role of stromal cell derived factor-1 in the recruitment of endothelial progenitor cells in endometriotic lesion angiogenesis, and the effects of the anti-angiogenic peptide ABT-898, a thrombospondin-1 mimetic, on endometriotic lesion growth and vascular development.