Heparins have been shown to be beneficial for the prevention of habitual miscarriages and repeated implantation failure, independently of their function as anticoagulants. The pro-inflammatory cytokine tumor necrosis factor (TNF)-α plays a role in the pathogenesis of these early pregnancy complications. Therefore, we examined the impact of heparin on TNF-α signaling in human endometrial stromal cells (ESCs) in vitro. Human ESCs were isolated from hysterectomy specimens and either used as undifferentiated cells or after decidualization in vitro. Cells were incubated with TNF-α, unfractionated heparin and signaling- and transporter-inhibitors. Interleukin (IL)-8 and -6 were measured using ELISAs and real-time RT–PCR. Nuclear factor of transcription (NF)-κB and its inhibitor IκBα were analyzed by in-cell western assays and confocal microscopy. Activation of NF-κB was determined in nuclear extracts using a specific transcription factor assay. Cellular internalization of heparin was detected by a heparin-uptake assay. Unfractionated heparin significantly suppressed the TNF-α-induced and NF-κB-mediated secretion and expression of IL-8 and -6 as well as other molecules in decidualized and undifferentiated human ESCs. Thereby heparin had no influence on the degradation of IκBα and the phosphorylation of NF-κB, but it inhibited the activity of NF-κB in the nucleus. An active heparin-uptake into the cells was the prerequisite for these heparin-effects. Unfractionated heparin is able to inhibit TNF-α/NF-κB-mediated inflammatory effects in the human endometrium independently of its classical function as an anticoagulant. These observations further underline on a molecular level the beneficial anti-inflammatory effects of heparin in women suffering from implantation disorders even in the absence of a thrombophilia.

(1) Background: Human milk oligosaccharides (HMOs) are already found in maternal circulation in early pregnancy, changing with gestational age. HMOs are also present in cord blood and amniotic fluid (AF). We aimed to assess HMO profiles in AF over the course of gestation. (2) Methods: AF was collected during diagnostic amniocentesis, fetal surgery, or C-section from 77 women with a gestational age of ranging from 14.3 to 40.9 weeks. Samples were analysed using high performance liquid chromatography with fluorescence detection. (3) Results: We found lactose and up to 16 HMO structures in all AF samples investigated, starting at 14 weeks of gestation. Overall, 3′-sialyllactose (3′SL) and 2′-fucosyllactose (2′FL) were the most abundant HMOs. Individual and total HMO concentrations were significantly positively correlated with gestational age. HMO composition also changed between early, mid- and late pregnancy, with relative concentrations of 3′SL significantly decreasing (44%, 25%, 24%) and 2′FL increasing (7%, 13%, 21%), respectively. (4) Conclusion: Our study shows that HMOs are already present in AF early in pregnancy. This demonstrates extensive contact of the fetus with a broad variety of HMOs, suggesting roles for HMOs in fetal tissue development during the time course of pregnancy.

Heparin modulates the decidualization of human endometrial stromal cells (ESCs), but the molecular mechanisms behind these effects are still unknown. In the present study, we further specified this biological effect of heparin in human ESCs in vitro. ESCs were isolated from hysterectomy specimens, decidualized over 12 days using progesterone and 17β-estradiol and incubated with thrombin, factor Xa (FXa), unfractionated heparin, dextran sulfate, danaparoid or different low-molecular-weight heparins (LMWHs). Production of insulin-like growth factor (IGF)-I, prolactin (PRL) and IGF-binding protein (IGFBP)-1 by ESCs was measured using ELISAs. Like heparin, thrombin and FXa cause an increase in IGF-I in ESCs, suggesting an action of heparin independent from its anticoagulatory effects. This was supported by demonstrating the induction of the same effects on IGF-I, PRL and IGFBP-1 as heparin by dextran sulfate, a polysaccharide of similar size and charge as heparin, but without anticoagulatory properties. LMWHs with the same anti-FXa activity as heparin showed less pronounced effects on ESCs than heparin, whereas the very short pentasaccharide fondaparinux (17 kDa) had barely any effect, further supporting the primary role of molecular size and charge mediating these biological effects of heparin on ESCs. In conclusion, the effects of heparin on the decidualization of human ESCs seem to be independent of its anticoagulatory function, but rather depend on the charge and the size of this polysulfated glycosaminoglycan. Therefore, highly sulfated polysaccharides with a molecular weight >17 kDa might be an interesting pharmacological approach for the therapy of endometrial pathologies, e.g. the treatment of women suffering from recurrent miscarriage or repeated implantation failure.

(1) Background: Pregnancy presents a challenge to maternal glucose homeostasis; suboptimal adaptations can lead to gestational diabetes mellitus (GDM). Human milk oligosaccharides (HMOs) circulate in maternal blood in pregnancy and are altered with GDM, suggesting influence of glucose homeostasis on HMOs. We thus assessed the HMO response to glucose load during an oral glucose tolerance test (OGTT) and investigated HMO associations with glucose tolerance/insulin sensitivity in healthy pregnant women. (2) Methods: Serum of 99 women, collected at 0 h, 1 h and 2 h during a 75 g OGTT at 24–28 gestational weeks was analyzed for HMOs (2′FL, 3′SLN, LDFT, 3′SL) by HPLC; plasma glucose, insulin and C-peptide were analyzed by standard biochemistry methods. (3) Results: Serum 3′SL concentrations significantly increased from fasting to 1 h after glucose load, while concentrations of the other HMOs were unaltered. Higher 3′SL at all OGTT time points was associated with a generally more diabetogenic profile, with higher hepatic insulin resistance (HOMA-IR), lower insulin sensitivity (Matsuda index) and higher insulin secretion (C-peptide index 1). (4) Conclusions: Rapid increase in serum 3′SL post-oral glucose load (fasted-fed transition) indicates utilization of plasma glucose, potentially for sialylation of lactose. Associations of sialylated HMOs with a more diabetogenic profile suggest sustained adaptations to impaired glucose homeostasis in pregnancy. Underlying mechanisms or potential consequences of observed HMO changes remain to be elucidated.

Steroid hormone imbalance is associated with the pathogenesis of preeclampsia. However, affected enzymes of steroid metabolism and gene and protein expression in serum and placenta have not been elucidated yet. We aimed to investigate steroid hormone profiles and precursor-to-product ratios in preeclamptic women compared to women with healthy pregnancy (controls) to identify potentially affected steroid hormones and their metabolizing enzymes. Also, we aimed to investigate whether the mRNA expression of these enzymes is different between the study groups and whether levels of serum mRNA expression reflect postnatal placental protein expression. Serum levels of 14 steroid hormones were measured at eight time points throughout pregnancy in nine preeclamptic women and 36 controls. Serum mRNA expression of selected steroid-metabolizing enzymes was assessed, and their protein expression was analyzed in additional nine preeclamptic women. Mean levels of sex steroid and corticosteroid hormones were significantly altered in preeclamptic women. Precursor-to-product ratios of 5α-reductase, aromatase and 11β-hydroxysteroid dehydrogenase 1 were significantly increased, those of steroid 17α-hydroxylase, 17β-hydroxysteroid-dehydrogenase, steroid 11β-hydroxylase and 11β-hydroxysteroid dehydrogenase 2 were significantly decreased. Serum mRNA expression and placenta protein expression were comparable between the groups. Results contribute to understanding the heterogeneity of preeclampsia and can thus promote future research in personalized medicine.