ABSTRACT
Fibroblast growth factors (FGFs) and their receptors are expressed in a variety of mammalian tissues, playing a role in development and cell proliferation. While analyzing human sperm motility, we found that sperm treated with endo-ß-galactosidase (EBG), which specifically hydrolyzes poly-N-acetyllactosamine type glycans (polyLacs), enhanced motility. Mass spectrometry analysis revealed that sperm-associated polyLacs are heavily fucosylated, consistent with Lewis Y antigen. Immunohistochemistry of epididymis using an anti-Lewis Y antibody before and after EBG treatment suggested that polyLacs carrying the Lewis Y epitope are synthesized in epididymal epithelia and secreted to seminal fluid. EBG-treated sperm elevated cAMP levels and calcium influx, indicating activation of fibroblast growth factor signaling. Seminal fluid polyLacs bound to FGFs in vitro, and impaired FGF-mediated signaling in HEK293T cells.
Subject(s)
Fibroblast Growth Factors/metabolism , Polysaccharides/physiology , Signal Transduction/physiology , Glycoside Hydrolases/pharmacology , HEK293 Cells , Humans , Male , Polysaccharides/metabolism , Protein Binding , Sperm Motility/drug effects , Spermatozoa/metabolismABSTRACT
OBJECTIVE: To determine whether the concentration of hCG in cervical fluid can predict miscarriage during early pregnancy. DESIGN: Prospective clinical study. SETTING: University hospital. PATIENT(S): Ninety-nine women with singleton pregnancies, 17 of whom suffered a miscarriage. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Miscarriage and the cervical fluid/serum hCG concentration ratio. RESULT(S): With a cutoff value of 1.0, the sensitivity, specificity, and positive and negative predictive values of the cervical fluid/serum hCG concentration ratio for predicting miscarriage were 88.2%, 94.9%, 83.3%, and 96.6%, respectively. CONCLUSION(S): The cervical fluid/serum hCG concentration ratio might be a useful predictor of miscarriage during early pregnancy.
Subject(s)
Abortion, Spontaneous/metabolism , Body Fluids/metabolism , Cervix Uteri/metabolism , Chorionic Gonadotropin/analysis , Chorionic Gonadotropin/metabolism , Female , Humans , Predictive Value of Tests , Pregnancy , Prospective Studies , Sensitivity and SpecificityABSTRACT
It has been reported that various structural and functional changes occur on the surface of the plasma membrane of the ovum and embryo during fertilisation and cleavage in preparation for implantation. Glycoproteins are thought to be one of the factors in cell attachment. Thus, we investigated the changes in glycoprotein expression on the cell surface membrane of the mouse embryo by using lectins. Among seven types of lectin (ConA, WGA, UEA-I, MPA, LCA, DBA and PNA), the fluorescent intensities of ConA and WGA markedly increased from unfertilised ova to blastocysts. By quantitative analysis using immuno-scanning electron microscopy, the numbers of ConA-gold particles were small until 4-cell cleavage, but increased significantly at the blastocyst stage. In contrast, an increased number of WGA-gold particles was detected even at the 4-cell stage, and this increase continued to the blastocyst stage. From the above observations, we conclude that the numbers of sugar chains bound to both ConA andWGA increases with blastocyst formation and earlier expression is observed with WGA. The present study dearly shows that glycoproteins on the cell membrane surface of the mouse embryo quantitatively increase at the time of implantation, and the possibility has been indicated that glycoproteins are involved in intercellular recognition and adhesion between the embryo and endometrial epithelium.
Subject(s)
Cleavage Stage, Ovum/physiology , Fertilization/physiology , Oligosaccharides/metabolism , Oocytes/metabolism , Animals , Cell Membrane/metabolism , Concanavalin A/metabolism , Lectins/metabolism , Mice , Microscopy, Electron, Scanning , Microscopy, Immunoelectron , Wheat Germ Agglutinins/metabolismABSTRACT
The aim of the present study was to elucidate functions of the interleukin (IL)-8 at ovulation and luteinization in vivo. To compare the morphological differences between human chorionic gonadotropin (hCG) and IL-8 stimulation, scanning electron microscopy was employed to study rat ovarian vascular corrosion casts. Follicular growth and increased capillary vessel densities around the follicles were seen in vascular corrosion casts after IL-8 injection, similar to the result of hCG administration. This result indicated that exogenous IL-8 could play a role in the neovascularization during follicular development as an angiogenetic factor. Many fenestrations were observed in the vascular endothelium by hCG administration. In contrast, no fenestrations were observed with IL-8 injection, indicating that IL-8 may not be sufficient to increase the vascular permeability directly. Although germinal vesicle breakdown (GVBD) occurred at rates of 82% after the hCG injection, only 20% GVBD was observed after the IL-8 injection. The present study indicated that IL-8 might have important effects on rat follicles at ovulation and luteinization via vascularization in a similar manner to hCG. However, IL-8 was not effective on vascular permeability and oocyte maturation, which were different from hCG. Thus, we can conclude that IL-8 can participate in follicular development in part and may play important roles in ovulation and luteinization as one of some mediators induced by endogenous luteinizing hormone.
