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Galectins are members of the mammalian β-galactoside-binding proteins, which recognize Galβ1-4GlcNAc sequences of several cell surface oligosaccharides. Plenty of galectins are already described in human tissue, especially in placenta. Here, gal-1-4, 7-10 and gal-12 were investigated systematically in trophoblast and decidua cells of first trimester placentas.Within this study, 15 first trimester placentas after induced abortion (7th-14th week of gestation) were examined with immunohistology and immunofluorescence based on a scoring system. Moreover, isolated and cultivated trophoblast cells from the first trimester were analyzed and evaluated for expression of gal-1-4, gal-7-10 and gal-12 at mRNA and protein level with real-time RT-Polymerase chain Reaction/PCR (Taq-Man). Double immunofluorescence with trophoblast specific markers identified galectin expressing cells at the feto-maternal interface.We could detect immunohistochemical staining of galectins 1-4, 7-10 and 12 in first trimester placenta: all examined galectins were found in the cytotrophoblast (CTB) and syncytiotrophoblast (SCT). Gal-1, -2, -3, -4, -7, -8, -9, -10 and -12 were identified in extravillous trophoblast cells (EVT) in immunohistology and immunoflourescence. The expression of gal-1, -9, -10, and gal-12 increased after 96h incubation in vitro without stimulation at mRNA level, while gal-2, -3, -4, -7 and -8 were decreased.This study describes a systematic analysis of the expression of gal-1-4, gal-7-10 and gal-12 in first trimester placentas and isolated trophoblast cells. Expression levels at mRNA level and the change within 96h cultivation in vitro indicate a possible influence on syncytium building of trophoblast cell on expression of galectins. Therefore, an interaction of galectins in vitro in syncytium building is possible.

Summary Perforin is a cytotoxic molecule which is found in high concentration at the fetomaternal interface. In this location, perforin is contained in a specialized subset of natural killer cells, called uterine NK cells. By the use of perforin-deficient mice, we studied the function of perforin in the pregnant uterus. Perforin-deficient mice, we studied the function of perforin in the pregnant uterus. Perforin-deficient mice were found to reproduce as efficiently as wild type controls; however, they differed from normal in that the frequency of uterine NK cells was significantly higher and these cells were found to proliferate during more advanced stages of pregnancy. Lipopolysaccharide, which caused a massive increase of fetal resorptions in C57BL/6 control mice when given intraperitoneally on day 6.5 of pregnancy, had the same effect in the perforin-deficient counterpart. This argues against uterine NK cells being effector cells in infection-mediated abortion. Furthermore, no differences in fertility were observed under restricted mating conditions and with severe social stress. However, when embryo transfer was performed, the implantation of blastocysts was achieved in unprepared endometrium of perforin-deficient mice, which was not possible in wild type controls of the same genetic background. This could argue for a role of perforin in the defense of the mother against undue pregnancies.

Emerging evidence reveals that the incidence of allergic disorders commencing during childhood is influenced by pre-, peri- and early postnatal environmental challenges. We here highlight biomarkers involved in the purported interaction of a challenged intrauterine environment during pregnancy and the risk for allergies in the children later in life. We propose that the identification of biomarkers during pregnancy may allow early detection of children prone to develop allergies and possibly other chronic immune diseases. Subsequently, therapeutic interventions designed to prevent negative consequences of prenatal environmental challenges on children's immune system would be within reach.

Background: Prenatal factors such as prenatal psychological stress might influence the development of childhood asthma. Methodology and Principal Findings: We assessed the association between maternal bereavement shortly before and during pregnancy, as a proxy for prenatal stress, and the risk of childhood asthma in the offspring, based on two samples of children 1–4 (n = 426 334) and 7–12 (n = 493 813) years assembled from the Swedish Medical Birth Register. Exposure was maternal bereavement of a close relative from one year before pregnancy to child birth. Asthma event was defined by a hospital contact for asthma or at least two dispenses of inhaled corticosteroids or montelukast. In the younger sample we calculated hazards ratios (HRs) of a first-ever asthma event using Cox models and in the older sample odds ratio (ORs) of an asthma attack during 12 months using logistic regression. Compared to unexposed boys, exposed boys seemed to have a weakly higher risk of first-ever asthma event at 1–4 years (HR: 1.09; 95% confidence interval [CI]: 0.98, 1.22) as well as an asthma attack during 12 months at 7–12 years (OR: 1.10; 95% CI: 0.96, 1.24). No association was suggested for girls. Boys exposed during the second trimester had a significantly higher risk of asthma event at 1–4 years (HR: 1.55; 95% CI: 1.19, 2.02) and asthma attack at 7–12 years if the bereavement was an older child (OR: 1.58; 95% CI: 1.11, 2.25). The associations tended to be stronger if the bereavement was due to a traumatic death compared to natural death, but the difference was not statistically significant. Conclusions/Significance: Our results showed some evidence for a positive association between prenatal stress and childhood asthma among boys but not girls.

Gestational diabetes mellitus (GDM) is defined as impaired glucose tolerance and affects 2%-8% of all pregnancies. Among other complications, GDM can lead to the development of type 2 diabetes mellitus (DM 2) in both mother and child. Peroxisome proliferator-activated receptors (PPARs) are major regulators of glucose and lipid metabolism. Furthermore, PPARs are mediators of inflammation and angiogenesis and are involved in the maternal adaptational dynamics during pregnancy to serve the requirements of the growing fetus. PPARs were originally named for their ability to induce hepatic peroxisome proliferation in mice in response to xenobiotic stimuli. The expression of three PPAR isoforms, alpha, beta/delta, and gamma, have been described. Each of them is encoded by different genes; however, they share 60%-80% homology in their ligand-binding and DNA-binding domains. PPARs are involved in trophoblast differentiation, invasion, metabolism, and parturition and are expressed in invasive extravillous trophoblast and villous trophoblast cells. Nuclear receptors, to which PPARs belong, are promising targets for disease-specific treatment strategies because they act as transcription factors controlling cellular processes at the level of gene expression and may produce selective alterations in downstream gene expression. To date, PPAR agonists are therapeutically used in patients with DM 2 and in patients with reproductive disorders such as polycystic ovary syndrome. Because of safety concerns and limited data, PPAR agonists are not yet included in GDM-related treatment strategies. Our objective herein is to review newly emerging generations of selective PPAR modulators and panagonists, which may have potent therapeutic implications in the context of GDM.

Recent in vitro and in vivo studies emphasize the impact of leptin, peroxisome proliferator-activated receptors (PPAR) and PPAR coactivators (retinoic X receptor a (RXR), amplified in breast cancer-3 gene (AIB3)) on placental and fetal development. Therefore, the frequency and distribution pattern of PPAR, RXR, AIB3 and leptin expression in normal human first trimester pregnancy, miscarriage and hydatidiform mole was investigated by immunohistochemistry and double immunofluorescence staining. Enhanced expression of PPAbeta/delta, RXR and AIB3 was identified in miscarried placentas. With regard to hydatidiform mole, increased expression of PPARgamma and PPARbeta/delta was observed, whereas RXR was significantly down-regulated. Leptin expression was lowest in miscarriage and highest in mole pregnancies. In contrast to trophoblast tissue, expression of leptin in glandular epithelial cells of the decidua was increased in miscarriage. PPAR and leptin expressing cells at the feto-maternal interface were identified as extravillous trophoblast (EVT) by double immunofluorescence and CK7 staining. In summary, significantly reduced leptin expression was accompanied by enhanced PPARbeta/delta, RXR and AIB3 expression in miscarried placentas. However, in mole pregnancy, up-regulation of leptin and increased expression of PPAR was detected. RXR, on the other hand, was down-regulated in mole decidua. So far, the study results implicate strong regulatory interaction of PPARs, their coactivators and leptin in human placentas. PPAR and leptin are potential targets for new treatment strategies concerning pregnancy disorders, such as miscarriage. The increasing knowledge about the role of PPARs and leptin in normal and disturbed pregnancy may help to improve pregnancy outcome.