Estrogen regulation of an eosinophil chemotactic factor in the immature rat uterus

Spatio-temporal distribution of eosinophils in the mouse uterus during peri-implantation period

Embryo implantation is an immunologically paradoxical event. In humans and rodents, blastocysts adhere to uterine epithelium and then invade into endometrial stroma, while maternal body is protected from extraneous materials by its immune system. Eosinophils, a kind of leucocytes involving parasitic infections and allergic response, increase in number in uterus when serum estrogen level is elevated during estrus cycles. However, response of uterine eosinophils to ovarian estrogen during peri-implantation period is not clear. Therefore, we investigated the distribution of eosinophils in murine peri-implantation uterus. On day 0.5 of pregnancy, eosinophils were found primarily in endometrial stroma near the luminal epithelium, whereas they were primarily distributed in basal endometrium and myometrium on day 3.5 of pregnancy. The number of uterine eosinophils on day 4.5 of pregnancy was significantly increased by inhibition of maternal estrogen action. Collectively, our results indicate that the ovarian estrogen negatively regulates uterine eosinophil distribution during peri-implantation period and provide insight into a role of maternal immune system in embryo implantation.

CCR3 antagonist impairs estradiol-induced eosinophil migration to the uterus in ovariectomized mice

Eosinophils are abundant in the reproductive tract, contributing to the remodeling and successful implantation of the embryo. However, the mechanisms by which eosinophils migrate into the uterus and their relationship to edema are still not entirely clear, since there are a variety of chemotactic factors that can cause migration of these cells. Therefore, to evaluate the role of CCR3 in eosinophil migration, ovariectomized C57BL/6 mice were treated with CCR3 antagonist SB 328437 and 17β-estradiol. The hypothesis that the CCR3 receptor plays an important role in eosinophil migration to the mouse uterus was confirmed, because we observed reduction in eosinophil peroxidase activity in these antagonist-treated uteruses. The antagonist also influenced uterine hypertrophy, inhibiting edema formation. Finally, histological analysis of the orcein-stained uteruses showed that the antagonist reduced eosinophil migration together with edema. These data showed that the CCR3 receptor is an important target for studies that seek to clarify the functions of these cells in uterine physiology.

Estrogen Signaling Modulates Allergic Inflammation and Contributes to Sex Differences in Asthma

Asthma is a chronic airway inflammatory disease that affects ~300 million people worldwide. It is characterized by airway constriction that leads to wheezing, coughing, and shortness of breath. The most common treatments are corticosteroids and β2-adrenergic receptor antagonists, which target inflammation and airway smooth muscle constriction, respectively. The incidence and severity of asthma is greater in women than in men, and women are more prone to develop corticosteroid-resistant or “hard-to-treat” asthma. Puberty, menstruation, pregnancy, menopause, and oral contraceptives are known to contribute to disease outcome in women, suggesting a role for estrogen and other hormones impacting allergic inflammation. Currently, the mechanisms underlying these sex differences are poorly understood, although the effect of sex hormones, such as estrogen, on allergic inflammation is gaining interest. Asthma presents as a heterogeneous disease. In typical Th2-type allergic asthma, interleukin (IL)-4 and IL-13 predominate, driving IgE production and recruitment of eosinophils into the lungs. Chronic Th2-inflammation in the lung results in structural changes and activation of multiple immune cell types, leading to a deterioration of lung function over time. Most immune cells express estrogen receptors (ERα, ERβ, or the membrane-bound G-protein-coupled ER) to varying degrees and can respond to the hormone. Together these receptors have demonstrated the capacity to regulate a spectrum of immune functions, including adhesion, migration, survival, wound healing, and antibody and cytokine production. This review will cover the current understanding of estrogen signaling in allergic inflammation and discuss how this signaling may contribute to sex differences in asthma and allergy.

Effect of prenatal exposure to lead on estrogen action in the prepubertal rat uterus

Lead is a widely spread environmental pollutant known to affect both male and female reproductive systems in humans and experimental animals and causes infertility and other adverse effects. The present paper investigated the effects of prenatal exposure to lead on different parameters of estrogen stimulation in the uterus of the prepubertal rat. In prenatally and perinatally exposed rats, estrogen-induced endometrial eosinophilia, endometrial stroma edema, and eosinophil migration towards the endometrium, and uterine luminal epithelial hypertrophy are enhanced while several other responses to estrogen appear unchanged. These effects may contribute to decrease in fertility following prenatal exposure to lead. The striking difference between most of these effects of prenatal exposure and the previously reported effects of chronic exposure to lead suggests that prenatal exposure to lead may neutralize the effects of chronic exposure to lead, providing partial protection of cell function against the adverse effects of chronic exposure to lead. We propose that the mechanism involved, named imprinting or cell programming, persisted through evolution as a nongenetic adaptive mechanism to provide protection against long-term environmental variations that otherwise may cause the extinction of species not displaying this kind of adaptation.

Estrogen-induced generation of reactive oxygen and nitrogen species, gene damage, and estrogen-dependent cancers

In addition to the direct effect of estrogen on mitochondria and the redox cycling of catechol estrogen, estrogen-induced proinflammatory cytokines, such as interleukin-1 beta (IL-1beta) and tumor necrosis factor alpha (TNF-alpha), also generate reactive oxygen and nitrogen species (RO/NS). Different cellular signaling pathways may operate in response to varying levels of estrogen-induced RO/NS, leading to genotoxic damage, cell apoptosis, or cell growth. At high levels of RO/NS, cells receiving genotoxic insults, if not repaired, may engage the apoptotic pathways. There is increasing evidence supporting that estrogen-induced alterations in the genome of cells is produced by oxidative attack. Furthermore, ROS generated by estrogen exposure and/or active metabolites of estrogen in combination with receptor-mediated proliferation of genetically damaged cells may be involved in tumor development. This view is supported by the findings of DNA modifications produced in vitro or in vivo by natural and synthetic estrogens in the target organs of cancer both in experimental models and in humans. Interaction of estrogen-induced oxidants and estrogen metabolites with DNA was shown to generate mutations in genes. Cotreatment with an inhibitor of IL-1beta and TNF-alpha synthesis, pentoxifylline, decreased stilbene estrogen-induced levels of myeloperoxidase (MPO), 8-hydroxydeoxyguanosine formation, and gene mutations, and prevented stilbene estrogen-induced lesions. Stable MCF-7 clones overexpressing IL-1beta resulted in a high level of IL-1beta peptide secretion undergoing cell apoptosis, and an elevated level of p53 protein in response to high oxidative stress when compared to nontransfected cells, whereas MCF-7 clones overexpressing IL-1beta that resulted in a moderate level of IL-1beta secretion stimulated the clonal expansion of MCF-7 and TM3 cells. Estrogen-induced MCF-7 cell growth and cyclin D1 expression were suppressed by antioxidants and mitochondrial blockers. These studies support that in addition to ovarian estrogen-mediated ER signaling, mitogenic signals may also come from estrogen-induced RO/NS. Further validation of this concept that the concentration of the RO/NS within the cellular microenvironment determines its stimulatory or inhibitory growth signals as well as its genotoxic effects regulating the growth of estrogen-dependent tumors may result in novel preventive strategies.

Genetic mapping of Eutr1, a locus controlling E2-induced pyometritis in the Brown Norway rat, to RNO5

In certain rat strains, chronic estrogen administration can lead to pyometritis, an inflammation of the uterus accompanied by infection and the accumulation of intraluminal pus. In this article, we report that the Brown Norway (BN) rat is highly susceptible to pyometritis induced by 17beta-estradiol (E2). The susceptibility of the BN rat to E2-induced pyometritis appears to segregate as a recessive trait in crosses to the resistant August x Copenhagen Irish (ACI) strain. In a (BN x ACI)F(2) population, we find strong evidence for a major genetic determinant of susceptibility to E2-induced pyometritis on rat chromosome 5 (RNO5). Our data are most consistent with a model in which the BN allele of this locus, designated Eutr1 (Estrogen-induced uterine response 1), acts in an incompletely dominant manner to control E2-induced pyometritis. Furthermore, we have confirmed the contribution of Eutr1 to E2-induced uterine pyometritis using an RNO5 congenic rat strain. In addition to Eutr1, we obtained evidence suggestive of linkage for five additional loci on RNO2, 4, 11, 17, and X that control susceptibility to E2-induced pyometritis in the (BN x ACI)F(2) population.

Localization of Eutr2, a locus controlling susceptibility to DES-induced uterine inflammation and pyometritis, to RNO5 using a congenic rat strain

In some rat strains chronic administration of exogenous estrogens induces pyometritis, an inflammation of the uterus associated with infection, suggesting that there is genetic variation in susceptibility to estrogen-induced inflammation and pyometritis. In this article we report that following 10 weeks of treatment with the synthetic estrogen diethylstilbestrol (DES), Fisher 344 (F344) rats exhibit modest uterine inflammation and a 0% incidence of pyometritis. By contrast, under identical experimental conditions, Brown Norway (BN) rats exhibit significant inflammation and a 100% incidence of pyometritis. Similarly, we also observed profound uterine inflammation and a 100% incidence of pyometritis in a congenic rat strain in which a segment of RNO5 from the BN strain is carried on the F344 strain. These data suggest that a locus on RNO5 controls both the magnitude of DES-induced uterine inflammation and susceptibility to DES-induced pyometritis. This locus, designated Eutr2, resides within the same segment of RNO5 as the Eutr1 locus, which confers susceptibility to E2-induced pyometritis in an F2 population generated in a cross between the BN and August x Copenhagen 9935, Irish (ACI) strains.

Dynamic profiling of estrogen receptor and epidermal growth factor signaling in the uteri of genistein- and estrogen-treated rats

The pharmacokinetics and time course actions of the soy isoflavone, genistein, and estradiol benzoate (EB) on sex steroid and growth factor signaling were compared in the rat uterus. Following one s.c. injection of 500 mg genistein/kg BW or 500 microg EB/kg BW, AUC for genistein was 20171.8 ng h/ml and was 15.7 ng h/ml for estradiol-17-beta. Estrogen receptor-alpha (ER-alpha) decreased within 2 h of genistein or EB treatment, returning to basal levels within 24 and 48 h, respectively. In response to genistein and EB, progesterone receptors (PRs) A and B increased between 16 and 24 h, with a significant increase at 24 and 48 h. Epidermal growth factor receptor (EGFR) expression peaked 16 h after genistein or EB treatment, inversely correlating with extracellular regulating kinase (ERK) phosphorylation. These effects were inhibited by antiestrogen pretreatment, demonstrating a requirement for ER. At 16 h, uterine weight, epithelial cell height, and cell proliferation increased. While EGFR levels increased, phosphorylated EGFR was not altered. Reduced phosphorylation of downstream kinases corresponded with decreased stromal phosphorylated-ERK (P-ERK) immunolabeling, suggesting signal attenuation. Dynamic profiling of sex steroid receptors and EGF signaling molecules suggest a similar mechanism of action for genistein and EB in the uterus, albeit at approximately 1000-fold concentration.

Vaginal and Cervical Dilatation Intrapartum is Associated with Eosinophilic Infiltration in the Cow but not in the Sheep

During parturition maximal dilatation of the vagina and cervix is necessary for expulsion of the neonate. The aim of the present study was to characterize the cell infiltration of the vagina and cervix that is associated with this event in cows and sheep. For this purpose, vaginal and cervical tissue were removed from four pluriparous cows and four sheep immediately after delivery of the neonate by biopsy under visual control (group 1), and the eosinophilic granulocytes were stained selectively. Four cows that were in interoestrus were used for control (group 2). In a third group of cows (n=10), blood samples were taken to determine the concentration of eosinophilic granulocytes from the fifth day antepartum up to the sixth day postpartum (group 3). A high degree of infiltration with eosinophilic granulocytes was detected in the bovine vagina and cervix intrapartum but not during interoestrus and in the ovine tissue intrapartum (p <0.001). In the bovine tissue, the cell density was higher in the vagina than in the cervix (p <0.05). The intrapartal tissue infiltration was associated with a short-term blood eosinopenia. In conclusion, this investigation demonstrates eosinophilic infiltration in the bovine vagina and cervix intrapartum, which differs from the situation in sheep. We suggest that this difference can be explained by the fact that cows deliver at high oestrogen and low progesterone values, but sheep show relatively high intrapartal P4 levels, which might suppress tissue infiltration with eosinophilic granulocytes.

Pleiotropic effects of Hoxa10 on the functional development of peri-implantation endometrium

Hoxa10, a homeodomain transcription factor, is dynamically expressed in adult uterine endometrium where it is necessary for embryo implantation. Endometrial Hoxa10 expression is driven by estrogen and progesterone. High levels of endometrial Hoxa10 expression coincide with high progesterone levels and development of endometrial receptivity. Although, progesterone is sufficient for endometrial differentiation and implantation, the molecular mechanisms by which progesterone mediates endometrial receptivity are not known. To determine if Hoxa10 mediates the developmental effects of progesterone in the endometrial cell compartments, we performed in vivo uterine transfection using pcDNA3.1/Hoxa10 in estrogen-primed, ovariectomized mice and compared results to mice treated with progesterone. Additional control mice were treated with either estrogen alone or empty vector pcDNA3.1. By using ovariectomized mice, we were able to determine specific developmental effects resultant from Hoxa10 treatment and distinguish them from those mediated by the regulation of multiple endogenous genes (including Hoxa10) by ovarian progesterone. Treatment with either Hoxa10 or progesterone resulted in diminished uterine weight and increased expression of characteristic cell-type specific differentiation markers such as epithelial calcitonin and stromal prolactin, suggesting that Hoxa10 likely mediates progesterone induced functional differentiation of endometrial epithelium and stroma. However, progesterone treatment suppressed endometrial eosinophil infiltration and degranulation compared to that seen with Hoxa10 treatment. Besides mediating progestational effects, Hoxa10 may activate distinct developmental pathways leading to endometrial differentiation. Functional differentiation in regenerative adult tissues may depend on timed expression of embryonic selector genes. Mol. Reprod. Dev. 67: 8-14, 2004.

Effect of chronic exposure to lead on estrogen action in the prepubertal rat uterus

Lead is a widely spread environmental pollutant known to affect both male and female reproductive systems in humans and in experimental animals. The present study investigated the effect of a chronic exposure to lead on different parameters of estrogen stimulation in the uteri of prepubertal rats. Chronic exposure to lead enhanced some parameters of estrogen stimulation, inhibited other estrogenic responses, while the remainder were unaltered. Estrogen-induced uterine eosinophilia (24 h), the proportion of uterine eosinophils in the mesometrium (6 h), and luminal epithelial hypertrophy and RNA content (24 h) appeared to be enhanced by lead exposure, compared to lead-unexposed control animals. Eosinophilia in the endometrium (6 h), the proportion of uterine eosinophils in the endometrium (6 and 24 h), edema in superficial and deep endometria (6 h), luminal epithelial hypertrophy (6 h), and mitotic response (cell proliferation) in all uterine cell types were inhibited by lead exposure, whereas circular myometrial hypertrophy was not significantly modified. The effects of lead exposure on responses to estrogen found in this study showed some differences with those previously reported for acute or subacute exposure to lead. The results revealed an interaction with the different mechanisms of estrogen action in the uterus at various levels, suggesting that some uterine cell types are more sensitive to lead than others. The relevance of the results for lead-induced infertility is discussed in this article, and possible mechanisms of action are proposed.

Estrogen-dependent growth of a rat pituitary tumor involves, but does not require, a high level of vascular endothelial growth factor

Long-term (10-week) treatment of Fischer 344 (F344) rats with the synthetic estrogen diethylstilbestrol (DES) increases the level of vascular endothelial growth factor (VEGF) in the pituitary. This is concurrent with the development of a large tumor of the pituitary of F344 rats. A role for VEGF in estrogen-dependent pituitary tumor growth is also supported by the fact that pituitary VEGF level is not increased by estrogen treatment in rats of the tumor-resistant Brown Norway (BN) strain. However, VEGF is not increased by estrogen treatment in an F(1) hybrid of F344 and BN, even though F(1) hybrid rats do form pituitary tumors in response to estrogen. Quantitative trait locus (QLT) mapping reveals that control of estrogen-dependent VEGF expression is linked to the Edpm5 QTL, which was previously identified as a QTL for estrogen-dependent pituitary tumor growth. In contrast, the QTL Edpm2-1 and Edpm9-2, which have been shown to each have a significant effect on estrogen-dependent pituitary mass of a magnitude similar to Edpm5, do not have any effect on VEGF level. Taken together, our results support the association of VEGF expression with growth of the estrogen-induced rat pituitary tumor, as has been reported by others, but they also indicate that there is significant pathways of growth regulation that are independent of high-level VEGF expression.

A simple method for the in situ detection of eosinophils

A simple and rapid method for identifying eosinophils in tissue sections is described. The assay is based on the incubation of frozen tissue sections with phenol red and the detection of cellular fluorescence. A one-to-one relationship was observed between cells exhibiting fluorescence following exposure to phenol red and eosinophils as identified by histochemical detection of eosinophil peroxidase (EPO) activity. Using the phenol red assay, eosinophils were detected in various eosinophil-infiltrated tissues, including uteri of rats from day 1 of pregnancy and uteri of prepubertal estrogen-treated rats. Intensity of the fluorescing eosinophils was dependent upon phenol red concentration and duration of incubation. The phenol red method of eosinophil identification was disrupted by co-incubation with resorcinol, an EPO inhibitor, or catalase, a hydrogen peroxide scavenger. The merits of this assay are its simplicity and compatibility with other procedures, such as histochemistry, immunocytochemistry, and in situ ligand-receptor binding.

Eotaxin is required for eosinophil homing into the stroma of the pubertal and cycling uterus

The presence of eosinophils in the endometrium of rodents during the estrous cycle or after E2 administration to ovariectomized animals is well documented. Nevertheless, the chemoattractant for eosinophils and the function of E-dependent eosinophils during the estrous cycle remain unknown. Using mice homozygous for a null mutation in the gene for eotaxin, a specific chemokine for eosinophils, we have identified eotaxin as being necessary for eosinophil homing into the uterine stroma, and regulated by E2 during the estrous cycle. In the absence of eosinophils, the onset of estrous cycle displayed a 2-wk delay along with the first age of parturition, suggesting a possible local role of eosinophils present in the pubertal uterus in preparing the mature uterus for pregnancy. However, despite the absence of eosinophils, once the mice reach maturity, their estrous cycles as well as their reproductive functions were normal. Our results demonstrate that E2 acts through eotaxin to recruit eosinophils to the uterine stroma during the estrous cycle in mice, but that these cells do not have a function in regulating either the duration of the estrous cycle or fertility of mice.

Monocyte chemotactic protein-1 and -2 messenger ribonucleic acids in the ovine uterus: regulation by pregnancy, progesterone, and interferon-tau

Endometrial leukocytes may play important roles during pregnancy. Because chemokines are regulators of immune cell activity and trafficking, this study determined if mRNAs for monocyte chemotactic proteins (MCP) were present in the ovine uterus and regulated by progesterone (P) and/or recombinant ovine interferon tau (roIFN-tau). Uteri of normal cycling and pregnant ewes (experiment 1) and uteri of ovariectomized ewes receiving intrauterine infusions of IFN-tau and/or i.m. injections of P (experiment 2) were used to detect MCP-1 and MCP-2 mRNA. In experiment 1, slot-blot hybridization analysis of endometrial total RNA revealed that MCP-1 and MCP-2 mRNA levels did not change during the estrous cycle but increased between Days 13 and 19 of pregnancy. Using in situ hybridization, MCP-1 and MCP-2 mRNA were localized to immune cells in the subepithelial compact stroma. Histomorphological studies and in situ hybridization for major basic protein (MBP) indicated that MCP-positive immune cells were eosinophils. In experiment 2, treatment with P and roIFN-tau increased (P < 0.05) the number of MCP-1- and MCP-2-expressing eosinophils in the endometrium compared to ewes treated with P alone. Injection of the P receptor antagonist (ZK 137,316) inhibited effects of P and/or roIFN-tau to recruit eosinophils expressing MCP-1 and MCP-2 mRNAs. Endometrial production of MCPs by eosinophils during early pregnancy may play a role(s) in central implantation and/or placentation in ewes that is crucial for successful establishment of pregnancy.

Fibroblasts and eosinophils in normal fibroplasia of ferret vulval skin, shown by light and electron microscopy; with special reference to eosinophil degranulation

In order to compare aspects of normal fibroplasia with reports for pathologically fibrotic tissue, light and electron microscopic observations were made on ferret vulval skin, which proliferates markedly with the onset of estrus and regresses equally fast after mating. Estrous tissue, which contained hypertrophied fibroblasts, new collagen, elastic fibers and ground substance, was invaded by numerous eosinophils with extensive release of granules. Eosinophil degranulation was both extra- and intracellular; some cells, completely disintegrated, had released all contents into the extracellular matrix. Extruded granules reacted positively for major basic protein. In regression, diminished fibroblasts incorporated collagen fibrils. Many of the features seen in this normal fibroplasia in ferret vulval skin are similar to those in pathologic situations. Thus, in particular, the presence of degranulating eosinophils in pathologic fibrosis does not necessarily indicate that they are the cause of the disease. Our information and that from other sources implies a role for eosinophils in connective tissue change.

Degranulating eosinophils in human endometriosis

Degranulating eosinophils have been described in most endometrial cancers. We hypothesized that endometriosis (ectopic, nonneoplastic endometrial tissue) would be an appropriate model system for determining whether eosinophil degranulation is part of a specific immune response to endometrial cancer or if it is related to the more general phenomenon of tissue remodeling (wound healing) that is common to both disorders. To test this hypothesis, we performed immunohistochemistry and Western blotting to evaluate the presence of eosinophil peroxidase (a marker of eosinophil degranulation) in normal endometrium (n = 20) and endometriosis samples (n = 24) and to define the coexpression of three eosinophil chemoattractants: interleukin-5 (IL-5), eotaxin, and regulated on activator-normal T cell expressed and secreted (RANTES). There was focally intense deposition of eosinophil peroxidase in the fibrotic connective tissue and blood vessels of 21 of 24 human endometriosis specimens; two samples showed weak staining, and only one tissue was negative for eosinophil degranulation. None of the 10 normal proliferative endometrial specimens had evidence of eosinophil degranulation, and four of 10 secretory tissues stained only weakly for eosinophil peroxidase. The presence of degranulating eosinophils was also associated with the presence of eotaxin and IL-5 in some samples and with RANTES in others. We conclude that the abundant presence of degranulating eosinophils in the fibrous regions of endometriosis supports the interpretation that eosinophils are involved in general tissue remodeling and wound healing rather than a tissue-directed immune response.

Role of relaxin and estrogen in the control of eosinophilic invasion and collagen remodeling in rat cervical tissue at term

Ripening and dilation of the rat cervix at term involves a widespread reduction in the density and organization of collagen fibers following a polymorphonuclear eosinophilic invasion. These are hormonally regulated events; however, the correlation between hormonal milieu and these morphological changes is not well understood. To investigate the role of preparturient relaxin and estradiol-17ss (E2) in cervical collagen remodeling and eosinophilic infiltration, pregnant rats were either sham-ovariectomized (group C) or ovariectomized in the morning of Day 22. Ovariectomized rats were treated with E2 (group OE), relaxin (group OR), E2 plus relaxin (group OER), or hormone vehicles (group O). There were 4 or 5 animals per group. Cervices were taken from animals killed approximately 1 h before expected parturition. Five-micrometer serial sections of paraffin-embedded cervices were stained with either Sirius Red in alkaline solution to measure eosinophil infiltration or in Picrosirius to measure collagen birefringence. Ovariectomized rats treated with E2 (group OE or OER) showed high levels of eosinophilic infiltration that did not differ from those in group C intact controls. However, the values of eosinophilic infiltration in ovariectomized rats treated with relaxin or hormone vehicles (groups OR and O) were low and far below (p < 0.01) those of groups OE and C. In ovariectomized rats treated with E2 alone (group OE), the widespread reduction in collagen organization that occurred in group C controls was not observed. It was only in ovariectomized rats treated with relaxin or E2 + relaxin (groups OR and OER) that the values of birefringence were low, and they were as low as in control group C. In conclusion, this study indicates that eosinophilic infiltration and collagen remodeling in the rat cervix at term are under the control of different hormones: E2 stimulates eosinophilic invasion, and relaxin promotes a widespread reorganization of collagen fibers.

The effect of progesterone on the accumulation of leukocytes in the human endometrium

OBJECTIVE

Our purpose was to determine the role of progesterone on the number and type of leukocytes found in human endometrium.

STUDY DESIGN

Endometrial tissue was obtained from normally cycling women and from women receiving hormone replacement therapy for premature ovarian failure. All tissues were formalin fixed, sectioned, and stained with specific antibodies to leukocytes, T cells, B cells, and macrophages. Each tissue was also dated by means of published techniques. Quantitation was performed by counting all immunopositive cells in five high-powered fields. Data were compared by analysis of variance and Mann-Whitney U test.

RESULTS

Leukocytes increased from 31.1 to 99.1 per high-powered field (p = 0.0001), and T cells increased from 10.9 to 20.4 per high-powered field (p = 0.001) after 12 days of progesterone treatment of women with ovarian failure. Normally menstruating women in the late luteal phase had similar concentrations. Neither B cells nor macrophages were found to increase with progesterone treatment.

CONCLUSIONS

These data indicate that progesterone results in an increased leukocyte and T-cell concentration in human endometrium.

Antiandrogenic property of RU 486: enhancement of estrogen-induced uterine peroxidase activity in the rat

The contragestational steroid RU 486 enhanced the increase in peroxidase activity produced by estradiol in estrogen-primed immature rat uteri and, like the antiandrogen flutamide, RU 486 reversed the inhibitory effect of testosterone on this estrogen-induced response. It antagonized the inhibition produced by progesterone but had no effect on peroxidase induction by itself or in unprimed immature animals. RU 486 also enhanced the effect of estradiol on the synthesis of complement component C3 in the rat uterus. The results confirm that RU 486 possesses antiandrogenic as well as antiprogestational properties. They also suggest that, in normal adult animals, the increase in peroxidase activity in the uterus in response to estrogen is not expressed fully but held in check by other endogenous steroids acting through their individual receptors.

Increased chemotactic activity of peritoneal fluid in patients with endometriosis

OBJECTIVE

Our purpose was to investigate the ability of the peritoneal fluid of patients with endometriosis to induce chemotaxis of neutrophils and macrophages.

STUDY DESIGN

Peritoneal fluid samples of patients with endometriosis (n = 20), normal fertile controls (n = 12), or patients with medical suppression (n = 8) were evaluated for chemotactic activity. Results of chemotactic activity were analyzed by analysis of variance.

RESULTS

Peritoneal fluid of patients with endometriosis demonstrated a significantly higher chemotactic activity than that of patients without endometriosis or with medical suppression. Patients who had received medical treatment had the lowest chemotactic activity. (p < 0.001 for endometriosis vs control or treatment patients, p = 0.005 for control group vs treatment group).

CONCLUSIONS

Patients with endometriosis have a higher chemotactic activity in their peritoneal fluid; prior medical treatment significantly reduces this activity. This chemotactic factor has an estimated weight of 20 kd. The nature and source of this chemotactic factor remains to be determined.

Immunohistochemical localization of the eosinophil major basic protein in the uterus horn and cervix of the rat at term and after parturition

Distribution of the eosinophil major basic protein (MBP) was studied in the rat uterus horn and cervix by means of immunohistochemistry using an antiserum raised against rat MBP. Various hormonal contexts were investigated: pre- and post-parturition, the estrous cycle, and ovariectomy followed by hormonal treatment or without treatment. MBP was detectable in the cervix as early as 12 h post-partum, appearing in the stroma close to the myometrium. The MBP had spread throughout the stroma toward the luminal epithelium after a few days. In contrast, no MBP was seen in sections of the corresponding pre- and post-partum uteri and in the pre-partum cervix. In cycling rats, MBP was distributed equally in the cervix and uterus and was more abundant during proestrus and estrus. In ovariectomized rats subsequently treated with progesterone, no MBP was detected in the cervix or uterus. In the cervix of ovariectomized rats treated with estradiol, MBP first appeared in the muscle layer situated between the two cervical lumina and then reached the stroma; within a few days only the stroma was stained. Inversely, in the uterus MBP-staining first appeared in the stroma. In conclusion, analysis of the distribution of MBP in rat uterus revealed a marked difference in the response of the cervix and horn to a hormonal environment.

Leukocyte chemotactic activity of FKBP and inhibition by FK506

Cyclophilin, the cyclosporin A binding protein and member of the immunophilin family of proteins, demonstrates leukocyte chemotactic activity. In this study we demonstrate that FKBP, the FK506 and rapamycin binding protein, also displays leukocyte chemotactic activity. The chemotactic activity of FKBP is inhibited by FK506, however, FK506 was unable to inhibit cyclophilin-stimulated chemotactic activity. Rapamycin was unable to prevent the chemotactic activity of FKBP, similarly, the CsA analogue Me6Ala-CsA while displaying cyclophilin binding was unable to block cyclophilin-stimulated chemotactic activity. These results suggest that in addition to their intracellular role the immunophilins may also function as chemotactic agents, furthermore this activity is modulated by immunosuppressants.

Complement C3 synthesis, peroxidase activity and eosinophil chemotaxis in the rat uterus: effect of estradiol and testosterone

Treatment of immature rats with estradiol (E2) produced a large increase in uterine peroxidase activity which was accompanied by an increase in eosinophil chemotactic factor (ECF-U). The synthesis of complement C3 was also induced in the uterus and the amount of this 180 kDa protein was determined both by immunoprecipitation and after separation by polyacrylamide gel electrophoresis. Testosterone (T) did not produce an increase in any of these parameters although it antagonized the estrogen-induced increase in uterine peroxidase activity and these effects were more pronounced in estrogen-primed animals. This antagonism was prevented by the antiandrogen, flutamide. Testosterone showed little effect on eosinophil chemotactic activity and did not inhibit the E2-stimulated synthesis of C3. The results with T were supported by the lack of any significant effect by flutamide which antagonizes receptor-mediated androgenic events. These findings are discussed in relation to the action of other types of hormonal steroids (progesterone, dexamethasone) in inhibiting these estrogen-induced molecular changes in the rat uterus and contribute to our understanding of steroid-steroid interaction and the regulation of uterine function.

Investigations concerning the relationship of ovarian eosinophilia to ovulation and luteal function in the sheep

Eosinophilic leukocytes are attracted into the preovulatory follicle and regressing corpus luteum of sheep. Eosinophils produce a wide array of potent bioactive substances that could play a role in ovarian function. Circulatory eosinophils were depleted by treatment of ewes with prednisolone, thereby producing ovarian eosinopenia. Ovulation occurred in these animals. However, circulatory concentrations of progesterone during the ensuing luteal phase were less than normal. This insufficiency was attributed in part to a suppressed angiogenic response in the formative corpus luteum. Regression of the corpus luteum induced by prostaglandin F2 alpha was not affected by administration of prednisolone. Thus, an obligatory role of eosinophils in the mechanics of ovulation and luteal regression in the sheep is unlikely.

Identification and tissue localization of an eosinophil 17 kDa protein accumulating in rat uterus upon estradiol treatment

In a previous paper (J. Steroid Biochem. 29 (1988) 475-480), the isolation of a 17 kDa protein that was dramatically induced in the uterus of estrogen-treated spayed rats was presented. We now describe a new purification procedure that is compatible with microsequencing of the 17 kDa protein. The protein partial N-terminal amino acid sequence analysis gave 28 residues that revealed a strong homology to the human major basic protein (MBP) of eosinophils described by Wasmoen et al. (J. Biol. Chem. 263 (1988) 12559-12563). Polyclonal rabbit antibodies were raised against this protein and used for tissue or blood cell analysis after electrophoresis and Western blotting. The 17 kDa protein was found to be constitutively present in the stomach and small intestine of the rat and guinea-pig. Estrogen treatment had a clearcut effect in guinea-pig uterus, but not as drastic as that observed in rat uterus. The protein was abundant in purified rat eosinophils. The antibodies cross-reacted with human MBP and an equivalent molecular weight human polymorphonuclear leukocyte protein. Immunohistochemical staining of rat uterus sections showed that the protein was first only associated with eosinophils that emigrate upon estrogen treatment; it then spread throughout the stroma and the deep glandular epithelium. It was not found in the myometrium. In conclusion, the appearance of a 17 kDa protein that is presumably the rat MBP is clearly regulated in the rat uterus.

Are eosinophil leucocytes involved in the oestrogenic response of the postnatal rat epididymis?

The effects of oestrogens and androgens, alone or in combination, on several epididymal parameters have been studied in 15-day-old rats after neonatal treatment. Oestrogens induced several responses, such as increased growth of the fibromuscular stroma and eosinophil leucocyte accumulation, whereas the proliferative activity of the epithelium was decreased significantly. Otherwise, the density of intra-epithelial leucocytes was not modified. Different oestrogen-induced responses, such as the increase in volume of the fibromuscular stroma and eosinophil leucocyte accumulation were inhibited by treatment with testosterone, whereas dihydrotestosterone had no appreciable effect. This study raises the possibility that eosinophils are mediators of some of the oestrogenic responses in the early postnatal rat epididymis.

Antagonism of estrogen- and antiestrogen-induced uterine complement component C3 expression by ICI 164,384

The uterus of the immature rat synthesizes and secretes complement component C3 in response to estradiol treatment. This response occurs in the uterine epithelial cells and is also stimulated by several antiestrogens including tamoxifen and LY117018. The administration of a new antiestrogen ICI 164,384 blocked the estradiol as well as the antiestrogen-stimulated increases in uterine weight, epithelial cell height, C3 synthesis and C3 mRNA. ICI 164,384 demonstrated no agonist properties in terms of epithelial cell response as determined by C3 expression.