Diet-induced obesity may affect the uterine immune environment in early-mid pregnancy, reducing NK-cell activity and potentially compromising uterine vascularization.

OBJECTIVES: To investigate the effect of obesity in early-mid pregnancy on crucial pregnancy hormones and the uterine immune environment. BACKGROUND: Obesity impacts reproductive ability, adversely affecting conception and leading to complications in pregnancy. Obesity is often regarded as a stress state and an immune disease, both of which may contribute to pregnancy failure. We previously demonstrated that stress in early pregnancy greatly alters progesterone secretion. As progesterone is an immunomodulator, altered progesterone secretion may adversely modify the maternal immune system. In the current study, we test the hypothesis that obesity during pregnancy adversely alters the uterine immune environment. METHODS: An obese mouse model was created by feeding C57/BL6 mice on a high-fat (HF)/sugar diet for 12 weeks before pregnancy. Control mice were fed on lower-fat/sugar chow. Mice were mated, and on day 7.5 of pregnancy plasma progesterone and prolactin were measured by immunoassay. Cells from the uterus-draining inguinal lymph nodes were collected for analysis of the uterine immune response by flow cytometry. RESULTS: Diet-induced obesity increased the secretion of progesterone and altered a number of uterine natural killer (NK)- and T-cell responses. These included a marked reduction in the percentage of leucocyte-derived NK cells and reduced expression of interferon-γ (IFN-γ) in the NK cells compared with control mice. CONCLUSIONS: Maternal obesity, induced by an HF diet, may lead to a reduction in the expression of IFN-γ in NK cells. NK-cell-derived IFN-γ is reported to be involved in supporting uterine spiral artery remodelling. Thus, obesity in early pregnancy may compromise vascularization by reducing the expression of IFN-γ-positive NK cells. Furthermore, the expression of uterine CD8(+) cells was reduced in the HF diet-fed mice, suggesting obesity may adversely alter the maternal immune adaptation that is essential for effective pregnancy.

Subclinical depressive symptoms affect responses to acute psychosocial stress in healthy premenopausal women.

Subclinical depressive symptoms constitute a primary risk factor for major depression as well as for cardiovascular conditions, which may be mediated by endocrine or immune alterations. The aim of this study was to assess the association between the extent of subclinical depressive symptoms and neuroendocrine and immune cell responses to acute psychosocial stress in healthy females. In N = 33 healthy premenopausal women, state anxiety, plasma adrenocorticotropic hormone and serum cortisol, and interleukin-6 (IL-6) concentration responses to public speaking stress were assessed. Beck depression inventory (BDI) scores were entered as a covariate in the analyses. The IL-6 response was significantly associated with BDI scores (p < 0.05). Secondary analyses revealed that women with more subclinical depressive symptoms demonstrated a reduced stress-induced increase in circulating IL-6 level (p < 0.05). By contrast, stress-induced neuroendocrine activation was not associated with depressive symptoms. Hence, subclinical depressive symptoms were associated with IL-6 responses to stress in young, healthy women. Unexpectedly, there was a reduced increase of serum IL-6 level in response to stress. Effects of depressive symptoms on the IL-6 response to stress may differ between subclinical and major depression.

Intraperitoneal immune cell status in infertile women with and without endometriosis.

Endometriosis is a widespread chronic disease characterized by endometrial tissue located outside the uterine cavity. Clinical signs are chronic pelvic pain and infertility. Emerging evidence indicates that the immune system is profoundly involved in the onset and/or progression of endometriosis. However, mechanistic pathways have not yet been conclusively specified. In this study, women undergoing diagnostic laparoscopy due to infertility were recruited, and classified as early-stage endometriosis (n=30), advanced-stage endometriosis (n=8) or no endometriosis (n=31). The frequency and phenotype of leukocytes were evaluated in peritoneal fluid. While the frequency of lymphocytes was not significantly different, neutrophils were increased in endometriosis. Flow cytometry analysis revealed an increased frequency of CD4(+) and CD8(+) cells in peritoneal fluid of endometriosis patients. In addition, the frequency of CD4(+)CD25(+)CD103(+) cells and lineage(-)HLA-DR(+)CD11c(+)CD123(+) dendritic cells was decreased in peritoneal fluid in endometriosis, whereas CD57(+) NK cells and CD8(+)CD28(-) T suppressor cells remained largely unaltered. We conclude that therapeutic approaches in endometriosis might focus on peritoneal leukocytes as a target or surveillance marker; however, immune alterations in peritoneal fluid are subtle and their analysis will require highly standardized and harmonized protocols.

Disturbed stress responses in women with polycystic ovary syndrome.

BACKGROUND: We analyzed the neuroendocrine and immune cell responses to psychosocial stress in PCOS patients compared to BMI-matched healthy controls. METHODS: Responses to public speaking stress were analyzed in 32 PCOS patients and 32 BMI-matched healthy controls. At baseline, during, and 10- and 45-min after stress, state anxiety, cardiovascular responses, cortisol, ACTH, as well as circulating leukocyte subpopulations were analyzed, together with hsCRP and serum IL-6 concentrations. RESULTS: In response to public speaking stress, both groups showed significant but comparable increases in state anxiety, and blood pressure (all p<0.001; time effects). The ACTH and cortisol stress responses were significantly enhanced in PCOS (both p<0.05; interaction effect). In addition, heart rate was significantly higher in PCOS (p<0.05; group effect). PCOS patients displayed a reduced upregulation of IL-6 levels in response to stress (p<0.05; interaction effect). Baseline levels of circulating leukocyte subpopulations, IL-6 and hsCRP concentrations did not differ between BMI-matched controls and PCOS patients. PCOS patients were characterized by markedly increased psychological distress. CONCLUSIONS: PCOS patients showed enhanced HPA-axis and heart rate reactivity as well as a reduced upregulation of IL-6 in response to stress. The altered stress reactivity in PCOS patients may constitute a link between depression, overweight, and the cardiovascular and diabetes risks associated with the diagnosis.

Effects of obesity on neuroendocrine, cardiovascular, and immune cell responses to acute psychosocial stress in premenopausal women.

OBJECTIVE: To analyze the neuroendocrine and immune cell responses to acute psychosocial stress in obese compared to non-obese premenopausal women. METHODS: N=15 obese (BMI> or =30) and N=24 (BMI<30) non-obese premenopausal women underwent public speaking stress. State anxiety, ACTH, cortisol, and the redistribution of immune cells were measured before, during, and 10 and 45min after public speaking. Serum hsCRP and serum IL-6 levels were analyzed before, and IL-6 additionally 45min after stress. RESULTS: In response to public speaking stress, both groups showed significant but comparable increases in state anxiety, plasma ACTH, and blood pressure (all p<0.01; time effects). The cortisol stress response was significantly enhanced in obese women (p<0.05; interaction effect). In addition, heart rate and diastolic blood pressure were significantly higher in obese women 10min following stress (p<0.05, t-tests). Public speaking stress led to a significant increase in IL-6 concentrations (p<0.001; time effect), and obese women displayed higher IL-6 levels both pre- and post-stress (p<0.05; group effect; between-group t-tests: pre-stress p<0.05; post-stress p<0.01). Baseline numbers of circulating leukocytes, granulocytes, CD3+ cells and hsCRP concentration were significantly higher in obese women (between-group t-tests: all p<0.05, but the groups did not differ in the stress-induced redistribution of circulating leukocyte subpopulations. CONCLUSIONS: Our data reveal a strong association of obesity with chronic low-grade inflammation in premenopausal women. This pro-inflammatory state, together with altered neuroendocrine and cardiovascular stress responsiveness, may conceivably constitute one of the mechanisms linking psychological stress and the long-term health risks associated with obesity.

Psychological implications of infertility in women with polycystic ovary syndrome.

BACKGROUND: In polycystic ovary syndrome (PCOS), one of the main features is chronic anovulation associated with lower pregnancy rates. Little is known regarding the psychological aspects associated with infertility in these patients. Therefore, we examined the influence of an unfulfilled wish to conceive on various aspects of psychological functioning in PCOS women. METHODS: Standardized questionnaires assessing quality-of-life (36-item short-form health survey, SF-36), depressiveness (Beck Depression Inventory), emotional distress (Symptom Check List 90, SCL-90-R), sexual satisfaction and self-worth (visual analogue scales), and a questionnaire on the desire for a child (FKW) were administered at the outpatient endocrine clinic to consecutive PCOS patients. RESULTS: Questionnaires from 115 PCOS patients were analysed. The majority (76.1%) worried about remaining childless in the future, and 51.3% reported a current wish to conceive. 23.9% of patients had scores indicating mild to moderate depression, and 25.2% had scores indicating clinically relevant depression. Furthermore, all quality-of-life scores were significantly lower compared with normative data (P < 0.001). Unexpectedly, comparisons of patients with a current unfulfilled desire to conceive to those with no present wish for a child revealed no discernable impact on depressive symptoms, quality-of-life or emotional distress. Reduced sexual satisfaction and self-worth were largely determined by partnership status and not infertility. However for PCOS patients who wished to conceive, the wish for a child was a significantly greater priority when compared with normative data from infertile patients. CONCLUSIONS: PCOS represents a major risk factor for psychosocial and emotional problems, but at least in this sample of PCOS patients, infertility does not appear to constitute a primary determinant of psychological problems.

Obesity, depression, and chronic low-grade inflammation in women with polycystic ovary syndrome.

BACKGROUND AND OBJECTIVE: Women with polycystic ovary syndrome (PCOS) present with multiple risk factors for cardiovascular diseases at a young age, including obesity and chronic low-grade inflammation. Since depression is common in PCOS, this study aimed to address whether depression correlates with indices of chronic low-grade inflammation beyond the association with obesity. METHODS: Serum concentrations of IL-6, the stimulated production of IFN-gamma, TNF-alpha, IL-2, IL-4, IL-5, and IL-10, leukocyte numbers, and hsCRP were analyzed in 57 PCOS patients and 28 healthy women, together with clinical parameters, including body mass index (BMI), testosterone, and insulin resistance (HOMA-IR), and psychological parameters, including Beck Depression Inventory (BDI) and health-related quality-of-life (SF-36) scores. RESULTS: PCOS patients demonstrated significantly increased hsCRP, IL-6, and leukocyte numbers. Group differences in IL-6 and leukocyte numbers, but not hsCRP, disappeared after controlling for BMI. The stimulated production of IFN-gamma, TNF-alpha, IL-2, IL-4, and IL-5 was significantly decreased, irrespective of BMI. In PCOS, hsCRP, IL-6, and leukocyte numbers were correlated with BMI, HDL, diastolic blood pressure, and with insulin resistance. On the other hand, no correlations were found with depression scores or with PCOS-specific endocrine abnormalities. In regression models, BMI was a significant predictor of the key immune markers, and explained a large amount of variance, whereas BDI was not included in either model. CONCLUSIONS: These data confirm that obesity plays a pivotal role in inflammatory processes relevant to cardiovascular risk in women with PCOS. However, even lean PCOS patients may display subtle alterations in specific aspects of immunity. Our findings did not support a correlation of depression with chronic low-grade inflammation in PCOS.

Social support during pregnancy: effects on maternal depressive symptoms, smoking and pregnancy outcome.

BACKGROUND: The goal was to study the effects of social support during pregnancy on maternal depressive symptoms, quality of life and pregnancy outcomes. METHODS: Eight hundred ninety-six women were prospectively studied in the first trimester of pregnancy and following completion of the pregnancy. The sample was divided into quartiles yielding groups of low, medium and high social support based on perceived social support. RESULTS: Pregnant women with low support reported increased depressive symptoms and reduced quality of life. The effects of social support on pregnancy outcomes were particularly pronounced in women who had smoked during pregnancy, with significant main effects of social support in a two-way analysis of variance (smoking status and social support) for child body length (F = 4.26, P = 0.04; 50.43 +/- 2.81 cm with low support versus 51.76 +/- 2.31 cm with high support) and birthweight (F = 11.35, P = 0.001; 3175 +/- 453 g with low support versus 3571 +/- 409 g with high support). In smokers, pregnancy complications occurred more frequently when given low support {34 versus 10.3% with high support, chi(2) = 5.49, P = 0.019; relative risk (RR) = 3.3 [95% confidence interval (95% CI) = 1.1-10.2]}, and the proportion of preterm deliveries was greater given low support (10.0 versus 0% with high support, chi(2) = 3.84, P = 0.05, odds ratio = 8.1). CONCLUSIONS: Lack of social support constitutes an important risk factor for maternal well-being during pregnancy and has adverse effects on pregnancy outcomes.

Patients with haematological malignancies show a restricted body image focusing on function and emotion.

The diagnosis of cancer threatens the psychological and bodily integrity. Based on this assumption, we aimed to explore how newly diagnosed patients cope with special regard to the body image (BI). In total, 40 patients (32 haematological malignancies) were assessed by questionnaires on mood, complaints, self-regulation and quality of life (QOL). The BI was assessed by the 'Body Grid' which reveals the constructs patients choose to characterize the body. The constructs were categorized using a model of six predefined categories comprising: emotion, control, activity, strength, function and appearance. Tinnitus sufferers and medical students served as comparison groups. Cancer patients showed significantly more anxious depression and a significantly lower QOL than controls. Their BI was restricted, focusing the functional status of body organs (e.g. opposing healthy vs. ill organs) as well as emotional aspects (e.g. trust vs. fear). The data convey fundamental psychological distress in newly diagnosed cancer patients. Restriction of BI and use of functional constructs may help to buffer the threat to body integrity. The emotional constructs reflect the existential impact. The data give a clear indication for the need for early psychosocial support which should aim at stabilizing the psychological and bodily integrity of the patient.

Nerve growth factor-induced substance P in capsaicin-insensitive vagal neurons innervating the lower mouse airway.

BACKGROUND: Nerve growth factor (NGF) is elevated in allergic diseases such as bronchial asthma and can lead to an induction of substance P (SP) and related neuropeptides in guinea-pigs large-diameter, neurofilament-positive airway neurons. OBJECTIVE: In the present study, the effect of NGF on tyrosine kinase receptor trkA and the capsaicin receptor TRPV1 expression in airway-specific vagal sensory neurons located in the jugular-nodose ganglia complex (JNC) of mice was investigated. METHODS: Using retrograde neuronal tracing in combination with double-labelling immunohistochemistry, SP, trkA- and TRPV1-receptor expression was examined in airway-specific sensory neurons of BALB/c mice before and after NGF treatment. RESULTS: NGF injected into the lower airway was able to induce SP (13.0+/-2.03% vs. 5.9+/-0.33%) and trkA expression (78+/-2.66% vs. 60+/-2.11%) in larger diameter (>25 microm), capsaicin-insensitive and trkA-positive vagal sensory neurons that were retrograde-labelled with Fast Blue dye from the main stem bronchi. CONCLUSION: Based on the extent of SP and trkA co-expression in airway-specific neurons by NGF treatment, the present study suggests that, following a peripheral activation of trkA receptor on SP afferent by NGF which is elevated in allergic inflammation, there may be trkA-mediated SP induction to mediate neurogenic airway inflammation.

Distribution of immunocompetent cells in decidua of controlled and uncontrolled (choriocarcinoma/hydatidiform mole) trophoblast invasion.

PROBLEM: Pregnancy has been considered as a model of successfully controlled tissue invasion where trophoblast cells infiltrate the maternal decidua without being rejected or without destroying the tissue. In choriocarcinoma (CC) and hydatidiform mole (HM), a dysregulation of invasive (malignant/benign) trophoblast cells is present. Immunocompetent cells (IC) are known to be involved in rejection pathways of malignant cells and can also be identified in early pregnancy decidua. The aim of the present study was to identify the phenotype of IC in decidua of women with normal pregnancy (NP), CC and HM. METHODS: Immunocompetent cells were detected by immunohistochemistry in decidual tissue from first trimester NP (n = 10), CC (n = 12) and HM (n = 11) using antibodies against CD8+, CD3+, CD56+, CD68+ cell surface markers and mast cell tryptase (MCT). A scaled eye piece was used for cell counting to obtain semiquantitative results. Statistical analysis was performed using Wilcoxon rank/Mann-Whitney tests. RESULTS: We observed a significantly increased number of lymphocytes positive for CD8, CD3 and MCT positive granulocytes in CC and HM compared with the samples from NP (all P < or = 0.001). Lymphocytes positive for natural killer (NK) cell marker CD56 were significantly decreased in CC and HM versus NP (P < or = 0.001). The number of CD68 positive cells (macrophages) were not significantly different among the tissue pools. CONCLUSION: The increase of CD8/CD3 T cells and mast cells in CC and HM and the decrease of CD56 cells, compared with NP, suggests the necessity of a balance between T and NK cells in controlling trophoblast invasion.

Heme oxygenases in pregnancy II: HO-2 is downregulated in human pathologic pregnancies.

PROBLEM: We previously reported a diminished expression of the heme-degrading enzymes heme oxygenases (HO)-1 and HO-2 in decidua and placenta from mice undergoing Th1-mediated abortion, strongly indicating the protective effect of HO in murine pregnancy maintenance. Here we investigated whether the expression of HO-1 and HO-2 is also reduced at the feto-maternal interface of pathologic human pregnancies. METHOD OF STUDY: Immunohistochemistry was used to detect HOs expression in placental and decidual first-trimester tissue from patients with: spontaneous abortion (n = 14), choriocarcinoma (n = 14), hydatidiform mole (H-mole) (n = 12), compared with normally progressing pregnancies (n = 15). Further, we investigated early third-trimester decidual and placental tissue from patients with pre-eclampsia (n = 13) compared with fetal growth retardation (n = 14) as age-matched controls. RESULTS: In first trimester tissue, we observed a significant reduction of HO-2 expression in invasive trophoblast cells, endothelial cells, and syncytiotrophoblasts in samples from patients with spontaneous abortion compared with normal pregnancy. H-mole samples showed a diminished expression of HO-2 in invasive trophoblast cells and endothelial cells in comparison with NP, whereas choriocarcinoma samples showed no significant differences compared with the control. In third trimester tissue, HO-2 was also reduced in syncytiotrophoblasts and invasive trophoblast cells from pre-eclampsia compared with samples from fetal growth retardation. HO-1 expression was diminished in all pathologies investigated; however, the differences did not reach levels of significance. CONCLUSIONS: Our data indicate that HOs play a crucial role in pregnancy and low expression of HO-2, as observed in pathologic pregnancies, may lead to enhanced levels of free heme at the feto-maternal interface, with subsequent upregulation of adhesion molecules, allowing enhanced inflammatory cells migration to the feto-maternal interface.

Th1 cytokines and the prothrombinase fgl2 in stress-triggered and inflammatory abortion.

PROBLEM: The immune system contributes to the outcome of pregnancy by complex immunological interactions. Cytokines especially influence the immune milieu pro or contra pregnancy. T helper 1 (Th1) cytokines [tumor necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma)] cause inflammation and together are thought to threaten the maintenance of pregnancy. It has been proposed that increased levels of these Th1 cytokines activate coagulation via up-regulating the novel prothrombinase, fgl2. This study further investigates the Th1 cytokine up-regulation of fgl2 expression in a pathophysiological, stress induced abortion model, and an inflammatory, interleukin-12 (IL-12) triggered abortion model. METHOD: The DBA/2J-mated CBA/J female mice were exposed to sonic sound stress or were injected with IL-12 during early gestation. On day 13.5 of pregnancy the uteri were removed and the resorption rate was calculated. We evaluated TNF-alpha, IFN-gamma, fgl2 as well as IL-12 messenger RNA (mRNA) expression in decidual samples of all mice by quantitative, real-time polymerase chain reaction (PCR). RESULTS: A similar resorption rate of 24% was detected in stressed mice, as well as in IL-12 injected mice compared with approximately 11% in non-stressed, non-injected control mice. In stressed mice compared with controls, we observed on day 13.5 up-regulated TNF-alpha, unchanged IFN-gamma down-regulated fgl2, and a slightly increased levels of IL-12. In the IL-12 triggered abortion model, we observed up-regulated levels of TNF-alpha, IFN-gamma and fgl2. CONCLUSION: These novel data suggest two distinct cytokine patterns leading to similar abortion rates. A physiological cascade associated with up-regulation of TNF-alpha, and an IL-12-triggered cascade characterized by persistent up-regulation of TNF-alpha and IFN-gamma as well as a persistent increase in fgl2.

Indications for a 'brain-hair follicle axis (BHA)': inhibition of keratinocyte proliferation and up-regulation of keratinocyte apoptosis in telogen hair follicles by stress and substance P.

It has long been suspected that stress can cause hair loss, although convincing evidence of this has been unavailable. Here, we show that in mice sonic stress significantly increased the number of hair follicles containing apoptotic cells and inhibited intrafollicular keratinocyte proliferation in situ. Sonic stress also significantly increased the number of activated perifollicular macrophage clusters and the number of degranulated mast cells, whereas it down-regulated the number of intraepithelial gd T lymphocytes. These stress-induced immune changes could be mimicked by injection of the neuropeptide substance P in nonstressed mice and were abrogated by a selective substance P receptor antagonist in stressed mice. We conclude that stress can indeed inhibit hair growth in vivo, probably via a substance P-dependent activation of macrophages and/or mast cells in the context of a brain-hair follicle axis.

Activation of the novel prothrombinase, fg12, as a basis for the pregnancy complications spontaneous abortion and pre-eclampsia.

PROBLEM: Impaired trophoblast invasion during the first trimester of pregnancy is linked to spontaneous abortion, and defective invasion in the second trimester to hypertension + proteinuria (pre-eclampsia). Hypertension developing during the third trimester of human pregnancy represents, in part, a corrective response in the mother to provide adequate placental perfusion for fetal growth when trophoblast has not to invaded and converted the myometrial porprtion of maternal spiral arteries into to low resistance-high capacitance conduits. Deportation of vesicles from hypoxemic trophoblast is thought to cause hypertension plus proteinuria, vascular damage and a systemic coagulopathy. Trophoblast invasion may be inhibited by local cytokines, such as TGF-betas but Thl-type cytokines associated with pre-eclapmsia and spontaneous abortions (e.g., IL-1, TNF-alpha, IFN-gamma) are not known to inhibit migration at in situ concentrations. Trophoblast invasion is also inhibited by the binding of surface integrins to fibronectin and fibrin, and fibrin production is stimulated by these Th1 cytokines via up-regulation of prothrombinases(s) such as fg12 which directly and via TNF-alpha-facilitated inflamation compromise trophoblast cell integrity. We, therefore, asked if fg12 expression and TNF-alpha are increased in first trimester human miscarriage and in third trimester pre-eclampsia. METHODS: fg12 mRNA was detected using in situ hybridization and fg12 protein by immunohistochemistry. TNF-alpha mRNA and protein were similarly tested. The techniques were validated using uterine sections from day 8.5 of CBA x DBA/2 pregnancies, and then were applied to sections of placentae from normal and pre-eclamptic pregnancies with and without intrauterine fetal growth restriction (IUGR). Fibrin was detectectd by immunohistochemistry. RESULTS: Expression of fg12 protein correlated with fg12 mRNA expression in mouse uteri and in placentae from normal human pregnancies. Increased expression of fg12 and TNF-alpha mRNA and protein, and increased fibrin deposition was detected in placental trophoblast. CONCLUSIONS: Activation of fg12 prothrombinase by Th1-type cytokines in pregnancy may lead to spontaneous abortion, or in ongoing pregnancy, to pre-eclampsia and/or IUGR.

Stress and pregnancy loss: role of immune mediators, hormones and neurotransmitters.

This review highlights recent studies investigating the impact of stress on pregnancy health or loss. Spontaneous abortion is the most common adverse pregnancy outcome, and stress has been suggested to be abortogenic in mice and humans. A wealth of information has been published on the effect of stress on the nervous, endocrine and immune systems during the past two decades. Stress- and/or pregnancy-related hormones (corticotropin releasing hormone, adrenocorticotropin, prolactin, and progesterone) might interact with peripheral and local immuncompetent cells, such as certain T cell subsets, mast cells or NK cells, and result in changes of cytokine production. Since a well-balanced interaction of nervous, endocrine and immune system is crucial for the maintenance of successful pregnancy, putative mechanisms and recent observations on stress-triggered pregnancy failure have been reviewed.

Murine stress-triggered abortion is mediated by increase of CD8+ TNF-alpha+ decidual cells via substance P.

PROBLEM: Stress is known to induce abortions in mice and humans. Increased levels of abortogenic type 1 helper T-cell cytokines and decreased levels of pregnancy protective cytokines could be linked to stress-triggered embryonic loss. Stress promotes neurotransmitter substance P (SP) release in tissues. SP increases the production of decidual tumor necrosis factor (TNF)-alpha, whereby the phenotype of these TNF-alpha-producing cells is hypothetical. The objective of the present study was to identify decidual TNF-alpha-producing cell populations that are involved in stress-induced murine abortion. METHOD: DBA/2J-mated CBA/J female mice were exposed to ultrasonic sound stress on day 5.5 of pregnancy. The mice were randomized and half were treated with the SP NK1-receptor antagonist (SP-RA) RP 67580 (200 microg/mouse). Frequency and cytokine profile of CD8+ cells were evaluated by immunohistochemistry and flow cytometry. Degranulation of uterine mast cells was examined histologically. RESULTS: On day 13.5 of pregnancy, the uteri were removed and the resorption rate was calculated. A mean resorption rate of 38.4% was detected in stressed mice (n = 10) compared to 13.1% in non-stressed control mice (n = 11, P < 0.01). Injection of SP-RA decreased the abortion rate to 18.4% in stressed mice (n = 19, P < 0.01). Flow cytometry revealed a stress-related increase of TNF-alpha+/CD8+ decidual T cells, which could be abrogated by SP-RA (P < 0.05). No significant differences could be observed in numbers of mast cells and total CD8+ cells in situ. CONCLUSION: Our data suggest that stress-triggered abortion is mediated by SP, and SP receptor blockade abrogates stress-triggered abortion via reduced production of TNF-alpha by CD8+ T cells.

Stress and immune mediators in miscarriage.

BACKGROUND: Stress is thought to be abortogenic and psycho-neuro-immunological pathways have been suggested to be involved in triggering miscarriages. From experiments in pregnant mice exposed to stress some insights into the underlying mechanisms have been gained, delineating immunological imbalances as a cause of pregnancy failure. In order to test the validity of the conclusions drawn from murine experiments and the role of stress in human pregnancy loss, the following study was performed. METHODS: We used an established perceived stress questionnaire and measured the stress score of women with a confirmed diagnosis of first trimester spontaneous abortion (n = 94). Decidual tissue was investigated by immunohistochemistry and in-situ hybridization to detect the presence and distribution of immunocompetent decidual cells [CD56(+) natural killer (NK) cells, CD8(+)and CD3(+) T cells, tryptase(+) mast cells (MCT(+)) and tumour necrosis factor (TNF)-alpha(+) cells]. The patient cohort was divided into women experiencing low or high levels of stress. RESULTS: In the decidua of women with high stress scores we observed significantly higher numbers of MCT(+), CD8(+) T cells and TNF-alpha(+) cells per mm(2) tissue (P < or = 0.05). No significant differences between individuals with lower or higher stress scores could be observed with respect to decidual CD56(+) NK and CD3(+) T cells. CONCLUSIONS: Using a questionnaire to score perceived stress in humans may be a valid approach to assess non-biased stress scores. Stress-triggered abortion in humans, identified by a questionnaire, can be linked to immunological imbalances.

Inhibition of dipeptidyl peptidase IV (DP IV, CD26) activity abrogates stress-induced, cytokine-mediated murine abortions.

In the CBA x DBA/2 mouse model, stress-triggered abortions are mediated by a Th1-like cytokine response of decidual lymphocytes. The factors that determine the cytokine pattern leading to abortion are currently unknown. Dipeptidyl Peptidase IV (DP IV) enhances Th1-cytokine responses and impairs the evolvement of a Th2 cytokine profile. The T-cell-activation antigen, CD26, possesses DP IV activity. The aim of the present study was to investigate the role of DP IV activity and CD26-positive decidual lymphocytes in murine stress-triggered abortions by inhibition of DP IV activity. DBA/2-mated CBA mice were stressed on day 5.5 of pregnancy and received daily injections of an inhibitor of DP IV activity, Ile-thiazolidide (20 micromol/kg). On day 13 of gestation, the animals were sacrificed and the percentage of implants and abortions documented. CD26-positive lymphocytes in spleen and uterine decidua and the intracellular cytokines interferon (IFN)-gamma and interleukin (IL)-10 were determined by flow cytometry. Stressed and nonstressed animals receiving an inactive stereoisomeric form were used as controls. In mice receiving the DP IV inhibitor, stress failed to boost the abortion rate (37.2% versus 13.6%, P < 0.01). IFN-gamma producing cells were increased in stressed animals, but returned to the baseline upon the inhibition of DP IV. The number of IL-10 producing cells was reduced in stressed animals, independent from DP IV inhibition.

Upregulation of decidual P-selectin expression is associated with an increased number of Th1 cell populations in patients suffering from spontaneous abortions.

A multicascade of leukocyte-endothelial cell interactions is involved in the trafficking of inflammatory lymphocytes into tissue. The primary contact between leukocytes and endothelium is mediated by selectins. Ligands for P-Selectin are preferentially expressed on Th1 cells and thereby allow migration of these inflammatory cells through the vessel wall. Since a peripheral and local Th1-type cytokine profile is present in spontaneous human abortion (SA), opposed by a Th2 dominant situation in normal pregnancies (NP), we investigated (1) the phenotype of peripheral Th1 cells by flow cytometry, as well as the Th1-type cytokine levels by ELISA, (2) the decidual expression of P- and E-Selectin by immunohistochemistry (IHC), and (3) the phenotype of decidual immunocompetent cells by IHC in patients with NP or SA. We observed enhanced production of IFN-gamma and TNF-alpha in CD8(+), CD3(+), and CD56(+) blood cells, as well as an increase in the number of CCR5(+) cells in patients suffering from SA compared to those with NP. No difference was detectable with respect to the serum levels of the two cytokines. Using IHC methods, we observed increased staining intensity of P-Selectin(+) vessels in samples of SA patients. E-Selectin was only weakly expressed in decidual endothelial cells, with no difference between NP and SA. In SA samples, E-Selectin(+) stromal cells were exclusively present. We further detected increased numbers of decidual CD8(+), CD3(+), CCR5(+), and CD56(+) cells in SA patients. We propose that Th1 lymphocyte migration into decidua is enhanced in SA due to upregulated P-Selectin expression in decidual vessels. This increase of Th1-producing lymphocytes might be involved in the rejection of trophoblasts.