ABSTRACT
The zona pellucida (ZP) is the extracellular matrix surrounding the mammalian oocyte. This matrix consists of three families called ZP1, ZP2 and ZP3. These proteins suffer several posttraductional modifications to give them different immunological and functional properties. In mice has been demonstrated the important role of ZP3 as a receptor of sperm. In the past, research in this field was limited for the difficulty to get enough biological material from different mammalian species, especially from human sources. Recently, several laboratories have expressed ZP recombinant proteins, allowing the study of the proteins under physiologic and pathophysiological conditions, giving the possibility to utilize ZP as a contraceptive target.
Subject(s)
Egg Proteins/physiology , Membrane Glycoproteins/physiology , Receptors, Cell Surface , Zona Pellucida/physiology , Animals , Female , Humans , Mice , Species Specificity , Sperm-Ovum Interactions/physiology , Vaccines, Contraceptive/immunology , Zona Pellucida GlycoproteinsABSTRACT
Vitamin D gained importance since the discovery of its steroid structure. Vitamin D participates in mineral homeostasis, regulation of gene expression, and cell differentiation. Recent advances in the study of the enzyme involved in the conversion of 25-hydroxyvitamin D3 into 1,25-dihydroxyvitamin D3 (calcitriol), as well as the discovery of it's hormone mechanism of action, have led to a better knowledge and understanding of vitamin D endocrine system, as well as it's implication in health and pregnancy.
Subject(s)
Vitamin D/physiology , 25-Hydroxyvitamin D3 1-alpha-Hydroxylase/physiology , Animals , Calcitriol/physiology , Calcium/metabolism , Calcium-Transporting ATPases/metabolism , Cell Differentiation , Disease Models, Animal , Endocrine System/physiology , Enzyme Activation , Enzyme Induction , Female , Fetus/metabolism , Gene Expression Regulation , Homeostasis , Humans , Infant, Newborn , Kidney Tubules, Proximal/enzymology , Male , Mice , Mice, Knockout , Minerals/metabolism , Nutritional Requirements , Placenta/metabolism , Pre-Eclampsia/metabolism , Pregnancy , Pregnancy Complications/metabolism , Receptors, Calcitriol/physiology , Rickets/metabolism , Vitamin D/chemistry , Vitamin D Deficiency/metabolismABSTRACT
We have evaluated the production of PRL by human peripheral mononuclear cells (PBMNC) from normal subjects and patients with systemic lupus erythematosus (SLE). Conditioned medium prepared from basal and Con-A-stimulated PBMNC was assessed for the presence of PRL-like by its ability to stimulate growth of PRL-responsive Nb2 rat lymphoma cells. In the presence or absence of Con-A, SLE PBMNC secrete significantly higher (P < 0.001) amounts of bioactive PRL-like species than normal cells. Growth of Nb2 cells by conditioned medium was inhibited with specific antiserum to human PRL. Western blotting using a polyclonal antibody to human PRL revealed a single 60-kDa PRL-like species in both normal and SLE PBMNC extracts, the immunoreactivity of which was preferentially found in SLE subjects. With the use of reverse transcription-PCR an expected 633-bp band was observed, and its similarity to pituitary PRL was further confirmed by Southern blot analysis with human PRL complementary DNA as a probe. We conclude that a high molecular mass PRL-like species is synthesized and secreted by PBMNC, and patients with SLE have an increased secretion of lymphocyte-derived PRL-like material.
Subject(s)
Leukocytes, Mononuclear/metabolism , Lupus Erythematosus, Systemic/blood , Prolactin/metabolism , Adolescent , Adult , Animals , Biological Assay , Blotting, Southern , Blotting, Western , Cells, Cultured , Concanavalin A/pharmacology , Culture Media, Conditioned , Female , Gene Expression , Humans , Lymphoma/pathology , Molecular Weight , Polymerase Chain Reaction , Prolactin/genetics , Prolactin/pharmacology , RNA, Messenger/analysis , RatsABSTRACT
The human testosterone-estradiol-binding globulin (hTeBG) is a plasma heterogeneous glycoprotein with high affinity for a number of circulating steroid hormones. The heterogeneity originates from differential glycosylation of a common protein precursor. Analysis of desialylated hTeBG by isoelectric focusing (IEF) has revealed that microheterogeneity could be partly attributed to variability in sialic acid content or rearrangement of amino acid composition. We have studied this possibility by the analysis of desialylated serum hTeBG by Western blotting of proteins previously separated on IEF-gels. Two distinct well-defined IEF patterns were identified. The most frequent consisted of two major IEF-bands of equal color intensity. The other pattern consisting of four IEF-bands was present in only 5.55% of the total serum samples analyzed. Family studies showed that these phenotypes were autosomally inherited with a simple Mendelian transmission and allele frequencies had an excellent agreement between the observed and expected phenotypes. Androgen affinity constants and serum concentrations of hTeBG variant were similar to those of normal hTeBG. Molecular analyses of each of the exons of hTeBG gene by denaturing gradient gel electrophoresis revealed the presence of a point mutation in exon 8. The studies presented herein confirm and extend previous reports on the existence of structural variants of hTeBG. In addition, the mutation reported in this study is probably the same as that recently identified within numerous ethnic groups throughout the world, thus further supporting the concept of a two allele gene worldwide concoding hTeBG.