Human Chorionic Gonadotrophin: New Pleiotropic Functions for an "Old" Hormone During Pregnancy.

Human chorionic gonadotrophin (hCG) is the first specific molecule synthesized by the embryo. hCG RNA is transcribed as early as the eight-cell stage, and the blastocyst produces the protein before its implantation. hCG in the uterine microenvironment binds with its cognate receptor, luteinizing hormone/choriogonadotropin receptor (LHCGR), on the endometrial surface. This binding stimulates leukemia inhibitory factor (LIF) production and inhibits interleukin-6 (IL-6) production by epithelial cells of the endometrium. These effects ensure essential help in the preparation of the endometrium for initial embryo implantation. hCG also effects angiogenic and immunomodulatory actions as reported in many articles by our laboratories and other ones. By stimulating angiogenesis and vasculogenesis, hCG provides the placenta with an adequate maternal blood supply and optimal embryo nutrition during the invasion of the uterine endometrium. The immunomodulatory properties of hCG are numerous and important for programming maternal immune tolerance toward the embryo. The reported effects of hCG on uterine NK, Treg, and B cells, three major cell populations for the maintenance of pregnancy, demonstrate the role of this embryonic signal as a crucial immune regulator in the course of pregnancy. Human embryo rejection for hCG-related immunological reasons has been studied in different ways, and a sufficient dose of hCG seems to be necessary to maintain maternal tolerance. Different teams have studied the addition of hCG in patients suffering from recurrent miscarriages or implantation failures. hCG could also have a beneficial or a negative impact on autoimmune diseases during pregnancy. In this review, we will discuss the immunological impacts of hCG during pregnancy and if this hormone might be used therapeutically.

Comparison between paraffin and mineral oil covering on early human embryo culture: a prospective randomized study.

The oil overlay in microdrop culture systems prevents medium evaporation, helps to maintain appropriate pH and osmotic conditions and protects from microbial contamination. In the present study, we prospectively compared covering by Ovoil™, a paraffin oil, and LiteOil®, a mineral oil, on the in vitro development of human embryos and their suitability for transfer/freezing at day 3 and live birth rate. One hundred and one patients undergoing in vitro fertilization (IVF) treatment by  intracytoplasmic sperm injection (ICSI) were enrolled in our study. After ICSI, 1237 oocytes were 1:1 randomly allocated into 2 groups according to the type of overlaying oil: Ovoil™ (616 oocytes) or LiteOil® (621 oocytes). Fertilization rate was assessed around 18 hours post-insemination (hpi) and embryos were checked for early cleavage at 25 hpi. Embryo morphology was recorded on days 2 and 3. A total of 437 (Ovoil™) and 438 day 3 embryos (LiteOil®) were analyzed. There were no differences between the two groups in terms of fertilization rate and occurrence of early cleavage. The proportion of top quality embryos (41.7% vs. 41.2%) and the final utilization rates (92.2% vs. 92.0%) were similar in Ovoil and LiteOil groups, respectively, at day 3. Live birth rate per transfer was essentially the same with Ovoil™ overlay (26.9%) when compared to LiteOil® (26.2%). Live birth rate in patients who simultaneously received  embryos from both overlay types was 17.2%. Despite the different characteristics of these two oils regarding hydrocarbon saturation, packing and temperature storage, Ovoil™ and LiteOil® can be used in parallel in the same IVF protocol. Abbreviations: ART: assisted reproductive technologies; hpi: hours post-insemination; hSA: human serum albumin; HTF: human tubal fluid; ICSI: intracytoplasmic sperm injection; IVF: in vitro fertilization; MII: metaphase II; MEA: mouse embryo assay; RT: room temperature.

Evidence for cross-talk between the LH receptor and LH during implantation in mice.

The present study investigated the first interaction that occurs between the blastocyst and endometrium during implantation. Given the ethical objections to studying implantation in humans, a mouse model was used to study the dialogue between luteinising hormone (LH) and luteinising hormone receptor (LHCGR). Several studies performed on LHCGR-knockout mice have generated controversy regarding the importance of the dialogue between LH and LHCGR during implantation. There has been no demonstration of a bioactive LH-like signal produced by the murine blastocyst. The first aim of the present study was to examine and quantify, using radioimmunoassay, the generation of a bioactive LH signal by the murine blastocyst. We went on to examine and quantify endometrial Lhcgr expression to validate the mouse model. Expression of LHCGR in mouse uteri was demonstrated using immunohistochemistry and western blot analysis. To quantify the expression of Lh in the mouse blastocyst and Lhcgr in the endometrium, reverse transcription-polymerase chain reaction (RT-PCR) and real-time quantitative (q) RT-PCR were performed. The results demonstrate that Lhcgr expression in BALB/c mouse endometrial epithelium is increased at the time of implantation and indicate that LHCGR may contribute to the implantation process. In support of this hypothesis, we identified a bioactive LH signal at the time of murine blastocyst implantation.

Isoform 111 of vascular endothelial growth factor (VEGF111) improves angiogenesis of ovarian tissue xenotransplantation.

BACKGROUND: Cryopreservation of cortex ovarian tissue before anticancer therapy is a promising technique for fertility preservation mainly in children and young women. Ischemia in the early stage after ovarian graft causes massive follicle loss by apoptosis. VEGF111 is a recently described vascular endothelial growth factor (VEGF) isoform that does not bind to the extracellular matrix, diffuses extensively, and is resistant to proteolysis. These properties confer a significantly higher angiogenic potential to VEGF111 in comparison with the other VEGF isoforms. METHODS: We evaluated the morphology of cryopreserved sheep ovarian cortex grafted in the presence or absence of VEGF111. Ovarian cortex biopsies were embedded in type I collagen with or without VEGF111 addition before transplantation to severe combined immunodeficient mice ovaries. Transplants were retrieved 3 days or 3 weeks later. Follicular density, vasculature network, hemoglobin content, and cell proliferation were analyzed. RESULTS: Addition of VEGF111 increased density of functional capillaries (P=0.01) 3 days after grafting. By double immunostaining of Ki-67 and von Willebrand factor, we demonstrated that proliferating endothelial cells were found in 83% of the VEGF111 group compared with 33% in the control group (P=0.001). This angiostimulation was associated with a significant enhancement of hemoglobin content (P=0.03). Three weeks after transplantation, the number of primary follicles was significantly higher in VEGF111 grafts (P=0.02). CONCLUSION: VEGF111 accelerates blood vessel recruitment and functional angiogenesis and improves the viability of ovarian cortex by limiting ischemia and ovarian cortex damage.

Hysteroscopic resection of abnormally invasive placenta residuals.

OBJECTIVE: To present our experience in hysteroscopic removal of abnormally invasive placenta (AIP) residuals using bipolar energy. DESIGN: Case series. SETTING: University hospital. POPULATION: Sixteen patients with AIP residuals after 17 pregnancies. METHODS: Cases were identified by ultrasound, treated with hysteroscopic bipolar electrosurgery and oral contraceptives, and followed up by ultrasound or hysteroscopy. Nine subsequent pregnancies were described. MAIN OUTCOME MEASURES AND RESULTS: Complete removal of AIP residuals was achieved by hysteroscopic bipolar electrosurgery in all cases except one. No perioperative complications occurred. AIP residual recurred in one patient after a subsequent pregnancy and was successfully treated using the same procedure. CONCLUSIONS: AIP residual is a rare condition. Management by hysteroscopic resection using bipolar energy is safe and feasible.

Hyperglycosylated human chorionic gonadotropin stimulates angiogenesis through TGF-ß receptor activation.

Embryo implantation requires extensive angiogenesis at the maternal-fetal interface. Hyperglycosylated human chorionic gonadotropin (hCG-H), a trophoblast invasive signal produced by extravillous cytotrophoblasts and by choriocarcinoma, was evaluated for its angiogenic role. hCG-H was purified by HPLC from choriocarcinoma supernatant, and the glycosylation pattern was determined by 2D gel analysis. Angiogenesis models used were aortic ring assay with wild-type and LHCGR-knockout mice, endothelial and mural cell proliferation, and migration assays. The TGF-ß signaling pathway was studied by coimmunoprecipitation, competitive binding, TGF-ß reporter gene assays, and Smad immunoblotting. hCG-H displayed a potent angiogenic effect [3.2-fold increase of number of vessel intersections in wild-type aortic rings (11.406 to 36.964)]. hCG-H-induced angiostimulation was independent of the classic hCG signaling pathway since it persisted in LHCGR-knockout mice [4.73-fold increase of number of vessel intersections (10.826 to 51.288)]. Using TGF-ß signaling inhibitors, Tß-RII was identified as the hCG-H receptor responsible for its angiogenic switch. hCG-H exposure enhanced phosphorylation of Smad 2 in endothelial and mural cells and genomic activation of Smad-responsive elements. Interaction between hCG-H and Tß-RII was demonstrated by coimmunoprecipitation and binding competition with (125)I-TGF-ß. This new paracrine interaction between trophoblast and endothelial cells through the hCG-H and the TGF-ß receptor complex plays a key role in angiogenesis associated with placental development and tumorigenesis.

Effects of oral contraception with ethinylestradiol and drospirenone on oxidative stress in women 18-35 years old.

BACKGROUND: Oral contraceptives (OCs) with estrogens and progestins may affect oxidative stress (OS) status. STUDY DESIGN: A group of 32 women using oral contraceptives (OCU) containing 0.03 mg ethinylestradiol and 3 mg drospirenone have been compared to a matched control group of 30 noncontraception users (NCU). Blood levels of antioxidants, trace elements and markers of lipid peroxidation were assessed by biochemical methods. A microarray analysis of whole blood mRNA levels of 200 genes involved in OS-dependant pathway was also performed. RESULTS: Levels of zinc, vitamin E and antibodies to oxidized low-density lipoproteins (LDLs) were not significantly different between the two groups. On the other hand, significant increases in the mean levels of lipid peroxides (+176%, p<.001), oxidized LDLs (+145%, p<.002), copper (+103%, p<.001), Cu/Zn ratio (+100%, p<.001) and a significant decrease in the mean level of beta-carotene (-41%, p<.01) were observed in the OCU compared to NCU. There was a highly significant positive correlation between the lipid peroxide levels and the copper-to-zinc ratio. From the 200 genes tested by microarray, one coding for HSP70 was significantly up-regulated (log(2) fold change=+ 0.45, p<.02) and one coding for inducible nitric oxide synthase significantly down-regulated (log(2) fold change=-0.24, p<.05) in the OCU compared to the NCU. CONCLUSIONS: The recently introduced combination of ethinylestradiol and drospirenone induced the heightening of lipid peroxidation correlated with high levels of copper, a situation that could be associated with increased cardiovascular risk.

Angiogenic activity of human chorionic gonadotropin through LH receptor activation on endothelial and epithelial cells of the endometrium.

Successful embryo development requires an extensive endometrial angiogenesis in proximity of implantation site. The glycoprotein hCG is produced even before implantation by trophoblast in normal pregnancy. In this manuscript, we demonstrate an angiogenic effect of hCG in several in vivo (chick chorioallantoïc membrane, matrigel plug assay, aortic ring assay) and in vitro experimental models. In contrast, human placental lactogen (hPL) did not display angiogenic properties. LH/hCG receptor was detected in endothelial cells by reverse-transcriptase polymerase chain reaction (RT-PCR) and by Western blotting. In mice aortic ring assay, angiostimulation by hCG was abrogated by deletion of LH/hCG receptor (LuRKO mice). Use of recombinant hCG and anti-hCG antibody (Ab) further confirmed the specificity of this angiogenic activity. By using dibutyryl cAMP, adenylate cyclase, or protein kinase A inhibitors, we demonstrate that hCG-mediated angiogenesis involves adenylyl-cyclase-protein kinase A activation. Addition of hCG to endometrial epithelial epithelial cells, but not to cultured endothelial cells, stimulated vascular endothelial growth factor (VEGF). VEGF and hCG also displayed additive activities. Altogether, these data demonstrate that peritrophoblastic angiostimulation may result from a paracrine dialogue between trophoblast, epithelial, and endothelial cells through hCG and VEGF.

Human endometrial leukemia inhibitory factor and interleukin-6: control of secretion by transforming growth factor-beta-related members.

OBJECTIVE(S): The implantation process is closely linked to the fundamental question of the tolerance of the maternal immune system. The main objective of this study was to investigate whether different members of the transforming growth factor-beta (TGF-beta) superfamily could intervene in the first steps of embryo implantation by modulating the secretion of proimplantatory leukemia inhibitory factor (LIF) and in the tolerance of the fetal graft by regulating proinflammatory interleukin (IL)-6 secretion by human endometrial epithelium (EEC) in vitro. METHODS: EEC were isolated from biopsies collected from 16 informed and consenting fertile women and were cultured for 72 h. Cytokine measurements (LIF and IL-6) were realized by ELISA. RESULTS: TGF-beta(1) (from 10(-12) to 10(-8)M), -beta(2), -beta(3) and activin A (10(-10) and 10(-8)M) increased LIF secretion by EEC cultures. Inhibin B (10(-10) and 10(-8)M) did not stimulate LIF production by human EEC. Contrastingly, TGF-beta(1) (from 10(-12) to 10(-8)M), -beta(2), -beta(3) and activin A (10(-10) and 10(-8)M) reduced IL-6 release by the same cells. Activin A at 10(-8) M also significantly reduced the stimulating effect of IL-1beta (10(-9)M) which is known to stimulate LIF production by EEC. Only the highest concentration of inhibin B (10(-8)M) reduced IL-6 secretion by EEC, but did not modulate IL-1beta-induced stimulation of IL-6 secretion. CONCLUSION(S): Besides their role in the control of the process of implantation and in the induction of embryonic mesoderm, different members of the TGF-beta superfamily may also contribute in the reproductive process by enhancing endometrial proimplantatory LIF secretion and reducing proinflammatory IL-6 release by EEC.

Expression pattern of metalloproteinases and tissue inhibitors of matrix-metalloproteinases in cycling human endometrium.

The cyclic growth, differentiation, and cell death of endometrium represents the most dynamic example of steroid-driven tissue turnover in human adults. Key effectors in these processes-matrix metalloproteinases (MMPs) and their specific inhibitors (TIMPs)-are regulated by ovarian steroids and, locally, by cytokines. We used reverse transcription-polymerase chain reaction to evaluate the expression of both transcriptionally regulated molecules such as estrogen receptor-alpha, progesterone receptor, and prolactin and a large array of MMPs and TIMPs (MMP-1, -2, -3, -7, -8, -9, -11, -12, -19, -26, MT1-MMP, MT2-MMP, MT3-MMP, TIMP-1, -2, -3). Altogether, three distinct patterns of MMP and two patterns of TIMP expression were detected in cycling endometrium: 1). MMPs restricted to the menstrual period (MMPs-1, -3, -8, -9, -12); 2). MMPs and TIMPs expressed throughout the cycle (MMP-2, MT1-MMP, MT2-MMP, MMP-19, TIMP-1, and TIMP-2); 3). MMPs predominantly expressed during the proliferative phase (MMP-7, MMP-11, MMP-26, and MT3-MMP); and 4). TIMP-3, which, contrary to the other TIMPs, shows significant modulations, with maximum expression during the late secretory and menstrual phases. These specific patterns of MMP expression associated with each phase of the cycle may point to specific roles in the processes of menstruation, housekeeping activities, angiogenesis, tissue growth, and extracellular matrix remodeling.