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1.
Biol Reprod ; 91(2): 31, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24899577

ABSTRACT

Adrenomedullin (ADM) may regulate seminal vesicle fluid secretion, and this may affect sperm quality. In this study, we investigated the effect of ADM on chloride secretion in the mouse seminal vesicle. The presence of ADM in mouse seminal vesicle was confirmed using immunostaining, and the molecular species was determined using gel filtration chromatography coupled with enzyme-linked assay for ADM. The effects of ADM on chloride secretion were studied by short-circuit current technique in a whole-mount preparation of mouse seminal vesicle in an Ussing chamber. The effects of specific ADM and calcitonin gene-related peptide (CGRP) receptor antagonists were investigated. Whether the ADM effect depended on the cAMP- and/or calcium-activated chloride channel was also studied using specific chloride channel blockers. The results showed that ADM was present in seminal vesicle epithelial cells. The major molecular species was precursor in the mouse seminal vesicle. ADM increased short-circuit current through the calcium-activated chloride channel in mouse seminal vesicle, and CGRP receptor was involved. We conclude that ADM may regulate chloride and fluid secretion from the seminal vesicle, which may affect the composition of the seminal plasma bathing the sperm and, hence, fertility.


Subject(s)
Adrenomedullin/metabolism , Chloride Channels/metabolism , Chlorides/metabolism , Seminal Vesicles/metabolism , Adrenomedullin/genetics , Animals , Carbazoles/pharmacology , Chloride Channels/antagonists & inhibitors , Cyclic AMP-Dependent Protein Kinases/antagonists & inhibitors , Cyclic AMP-Dependent Protein Kinases/metabolism , Electrophysiological Phenomena/physiology , Gene Expression Regulation/drug effects , Gene Expression Regulation/physiology , Male , Mice , Mice, Inbred C57BL , Pyrroles/pharmacology , ortho-Aminobenzoates/pharmacology
2.
Andrology ; 2(3): 474-80, 2014 May.
Article in English | MEDLINE | ID: mdl-24711244

ABSTRACT

In this study, we have investigated the effects of adrenomedullin on chloride and fluid secretion in the rat prostate. The presence of adrenomedullin (ADM) in rat prostate was confirmed using immunostaining, and the molecular species was determined using gel filtration chromatography coupled with an enzyme-linked assay for ADM. The effects of ADM on fluid secretion were studied by short-circuit current technique in a whole mount preparation of the prostate in an Ussing chamber. The results indicated that the ADM level was higher in the ventral than the dorso-lateral prostate and the major molecular species was the active peptide. ADM increased the short-circuit current through both the cAMP- and calcium-activated chloride channels in the ventral lobe, but only through the calcium-activated channels in the dorso-lateral lobe. These stimulatory effects were blocked by the calcitonin gene-related peptide (CGRP) receptor antagonist, hCGRP8-37. We conclude that ADM may regulate prostatic fluid secretion through the chloride channels, which may affect the composition of the seminal plasma bathing the spermatozoa and hence fertility.


Subject(s)
Adrenomedullin/metabolism , Calcium Channels/metabolism , Chloride Channels/metabolism , Semen/metabolism , 4,4'-Diisothiocyanostilbene-2,2'-Disulfonic Acid/pharmacology , Animals , Calcitonin Gene-Related Peptide/pharmacology , Calcitonin Gene-Related Peptide Receptor Antagonists , Calcium Channel Blockers/pharmacology , Carbazoles/pharmacology , Chloride Channels/antagonists & inhibitors , Cyclic AMP/biosynthesis , Cyclic AMP-Dependent Protein Kinases/antagonists & inhibitors , Enzyme Inhibitors/pharmacology , Male , Nifedipine/pharmacology , Peptide Fragments/pharmacology , Prostate , Pyrroles/pharmacology , Rats , Rats, Sprague-Dawley , ortho-Aminobenzoates/pharmacology
3.
Biol Reprod ; 89(4): 99, 2013 Oct.
Article in English | MEDLINE | ID: mdl-23966326

ABSTRACT

The oviduct serves as a site for the fertilization of the ovum and the transport of the conceptus down to the uterus for implantation. In this study, we investigated the presence of adrenomedullin (ADM) and its receptor component proteins in the pig oviduct. The effect of ADM on oviductal secretion, the specific receptor, and the mechanisms involved were also investigated. The presence of ADM and its receptor component proteins in the pig oviduct were confirmed using immunostaining. Short-circuit current (I(sc)) technique was employed to study chloride ion secretion in the oviductal epithelium. ADM increased I(sc) through cAMP- and calcium-activated chloride channels, and this effect could be inhibited by the CGRP receptor antagonist, hCGRP8-37. In contrast, the nitric oxide synthase inhibitor, L-NG-nitroarginine methyl ester (L-NAME), could not block the effect of ADM on I(sc). In summary, ADM may increase oviductal fluid secretion via chloride secretion independent of the nitric oxide pathway for the transport of sperm and the conceptus.


Subject(s)
Adrenomedullin/metabolism , Calcium Signaling , Cell Membrane/metabolism , Chloride Channels/metabolism , Cyclic AMP/metabolism , Oviducts/metabolism , Receptors, Calcitonin Gene-Related Peptide/metabolism , Adrenomedullin/analogs & derivatives , Animals , Calcitonin Gene-Related Peptide/pharmacology , Calcitonin Gene-Related Peptide Receptor Antagonists , Calcium Signaling/drug effects , Cell Membrane/drug effects , Chloride Channels/antagonists & inhibitors , Cyclic AMP/antagonists & inhibitors , Enzyme Inhibitors/pharmacology , Estrus , Female , Humans , In Vitro Techniques , Membrane Potentials/drug effects , Membrane Transport Modulators/pharmacology , Nitric Oxide/antagonists & inhibitors , Nitric Oxide/metabolism , Nitric Oxide Synthase/antagonists & inhibitors , Nitric Oxide Synthase/metabolism , Oviducts/cytology , Oviducts/drug effects , Patch-Clamp Techniques , Peptide Fragments/pharmacology , Receptors, Adrenomedullin/antagonists & inhibitors , Receptors, Adrenomedullin/metabolism , Second Messenger Systems/drug effects , Sus scrofa
4.
J Clin Endocrinol Metab ; 97(6): 2105-12, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22456622

ABSTRACT

CONTEXT: Tubal ectopic pregnancy (tEP) is currently the leading cause of pregnancy-related deaths during the first trimester. Our current knowledge on the molecular pathogenesis is limited. OBJECTIVE: The objective of the study was to find out the possible role of adrenomedullin (ADM) in the pathogenesis of tEP. DESIGN: This was an experimental in vitro study on oviductal tissue. SETTING: The study was conducted at a university teaching hospital. PATIENTS AND INTERVENTIONS: Patients included those having oviducts removed surgically during salpingectomy for tEP or hysterectomy for benign gynecological conditions. Oviductal tissues were incubated in hormonal condition mimicking early pregnancy before used for in vitro experiments. MAIN OUTCOME MEASURES: Plasma ADM concentration, oviductal expression of ADM and its receptors, ciliary beat frequency, smooth muscle contraction were measured. RESULTS: The ciliary beat frequency and frequency of muscle contraction were lower in the oviducts from patients with tEP than those from simulated normal pregnancy. The plasma and oviductal tissue ADM levels were also lower. The decreases in ciliary beat and frequency of contraction were restored to normal after ADM treatment. CONCLUSIONS: The results suggest that the lower ADM level in the oviducts of tEP may lead to the decrease in ciliary beating and muscle contraction, with the result that the embryo is retained and implanted in the oviduct. Our findings explain for the first time the etiology of tubal pregnancy on the basis of an impairment of the transport of the fertilized ovum resulting from an ADM deficiency and raise the possibility of using the plasma ADM level as a predictor for tubal ectopic pregnancy.


Subject(s)
Adrenomedullin/physiology , Fallopian Tubes/physiology , Pregnancy, Tubal/etiology , Pregnancy, Tubal/physiopathology , Adrenomedullin/blood , Adrenomedullin/genetics , Adult , Biomarkers/blood , Cilia/physiology , Embryo Implantation/physiology , Female , Gene Expression/physiology , Humans , Middle Aged , Muscle, Smooth/physiology , Predictive Value of Tests , Pregnancy , Pregnancy, Tubal/blood , Receptors, Adrenomedullin/genetics , Receptors, Adrenomedullin/physiology
5.
Endocrine ; 41(2): 256-65, 2012 Apr.
Article in English | MEDLINE | ID: mdl-22042486

ABSTRACT

In this study, the gene expression of adrenomedullin (Adm) in the peripheral tissues which include lung, adrenal, kidney, and heart during development was investigated in the rat. The preproadrenomedullin (preproAdm) mRNA and mRNAs of its related receptor components, calcitonin receptor-like receptor (Crlr), and receptor activity-modifying proteins (Ramp1, 2 and 3) of the lung, adrenal, kidney, and heart were measured by real-time RT-PCR and the ADM peptide measured by radioimmunoassay in 1-, 7-, 21-day-old rats and the adult rats. From day 1 to 21, preproAdm mRNA levels increased with age in the lung, the kidney, and the heart but decreased with age in the adrenal. ADM levels, however, increased with age in the lung but decreased with age in the kidney, the adrenal, and the heart. The preproAdm levels in the lung, in the kidney, and in the adrenal all increased in the adult rat. ADM peptide levels, however, decreased in the adult rat. Crlr and Ramp2 gene expression increased with age in the lung, in the kidney, and in the heart but decreased with age in the adrenal in the prepubertal rats. The results indicate that the levels of preproAdm mRNA, ADM peptide and its receptor component mRNAs in different tissues followed different patterns of changes during development.


Subject(s)
Adrenomedullin/metabolism , Gene Expression Regulation, Developmental , Kidney/growth & development , Kidney/metabolism , Adrenal Glands/growth & development , Adrenal Glands/metabolism , Adrenomedullin/genetics , Animals , Animals, Newborn , Calcitonin Receptor-Like Protein/genetics , Calcitonin Receptor-Like Protein/metabolism , Female , Heart/growth & development , Lung/growth & development , Lung/metabolism , Male , Myocardium/metabolism , Organ Specificity , Protein Isoforms/genetics , Protein Isoforms/metabolism , Protein Precursors/genetics , Protein Precursors/metabolism , RNA, Messenger/metabolism , Rats , Rats, Sprague-Dawley , Receptor Activity-Modifying Proteins/genetics , Receptor Activity-Modifying Proteins/metabolism , Receptors, Adrenomedullin/genetics , Receptors, Adrenomedullin/metabolism
6.
Reproduction ; 141(3): 367-72, 2011 Mar.
Article in English | MEDLINE | ID: mdl-21173072

ABSTRACT

Our laboratory previously showed that oviduct produced the greatest amount of adrenomedullin (ADM) in the rat female reproductive tract. The aim of this study is to investigate the changes in ADM levels resulting from the contact between the sperm and the oviduct and the possible roles of ADM in ciliary beating and oviductal contractility. Oviducts from Sprague-Dawley rats removed at pre- and post-ovulatory stages were cut open longitudinally and treated with ADM and/or receptor blockers before ciliary beat frequency (CBF) was measured. The effects of sperm on ADM production and CBF in the oviduct were also determined. The contraction of the oviduct after treatment with ADM and receptor antagonists was measured using the organ-bath technique. The results showed that ADM increased the CBF in rat oviduct and this stimulating effect was blocked by the calcitonin-gene-related peptide (CGRP) receptor antagonist, hCGRP(8-37). CBF was lower in post-ovulatory than pre-ovulatory oviducts. The presence of sperm in the oviduct increased both the ADM level and CBF. ADM treatment was shown to inhibit the contractility of the oviduct by lowering the basal tone and decreasing the contraction amplitude. The ADM receptor antagonist, hADM(22-52), was effective in counteracting the relaxation effect of ADM in the oviduct. All in all, these results indicate that ADM may play a crucial role in transporting the gametes/embryos by regulating ciliary beating and muscular contraction.


Subject(s)
Adrenomedullin/pharmacology , Cilia/drug effects , Fallopian Tubes/drug effects , Movement/drug effects , Muscle Contraction/drug effects , Adrenomedullin/genetics , Adrenomedullin/metabolism , Adrenomedullin/physiology , Animals , Cell Movement/drug effects , Cell Movement/genetics , Cilia/metabolism , Cilia/physiology , Down-Regulation/drug effects , Embryo, Mammalian/drug effects , Embryo, Mammalian/physiology , Fallopian Tubes/cytology , Fallopian Tubes/metabolism , Fallopian Tubes/physiology , Female , Gene Expression , Germ Cells/cytology , Germ Cells/drug effects , Germ Cells/physiology , Male , Rats , Rats, Sprague-Dawley , Spermatozoa/physiology , Up-Regulation/drug effects
7.
Endocrinology ; 151(7): 3336-47, 2010 Jul.
Article in English | MEDLINE | ID: mdl-20444935

ABSTRACT

Cilium and flagellum beating are important in reproduction and defects in their motion are associated with ectopic pregnancy and infertility. Adrenomedullin (ADM) is a polypeptide present in the reproductive system. This report demonstrates a novel action of ADM in enhancing the flagellar/ciliary beating of human spermatozoa and rat oviductal ciliated cells. At the concentration found in the seminal plasma, it increases the progressive motility of spermatozoa. ADM binds to its classical receptor, calcitonin receptor-like receptor/receptor activity-modifying protein complex on spermatozoa. ADM treatment increases the protein kinase A activities, the cyclic adenosine monophosphate, and nitric oxide levels of spermatozoa and oviductal cells. Pharmacological activators and inhibitors confirmed that the ADM-induced flagella/ciliary beating was protein kinase A dependent. Whereas nitric oxide donors had no effect on sperm motility, they potentiated the motility-inducing action of protein kinase A activators, demonstrating for the first time the synergistic action of nitric oxide and protein kinase A signaling in flagellar/ciliary beating. The ADM-induced motility enhancement effect in spermatozoa also depended on the up-regulation of intracellular calcium, a known key regulator of sperm motility and ciliary beating. In conclusion, ADM is a common activator of flagellar/ciliary beating. The study provides a physiological basis on possible use of ADM as a fertility regulation drug.


Subject(s)
Adrenomedullin/pharmacology , Cyclic AMP-Dependent Protein Kinases/metabolism , Cyclic AMP/metabolism , Nitric Oxide/metabolism , Oviducts/drug effects , Oviducts/metabolism , Sperm Motility/drug effects , Adrenomedullin/metabolism , Animals , Calcium/metabolism , Cyclic AMP-Dependent Protein Kinases/antagonists & inhibitors , Female , Humans , In Vitro Techniques , Isoquinolines/pharmacology , Male , NG-Nitroarginine Methyl Ester/pharmacology , Nitric Oxide Donors/pharmacology , Nitric Oxide Synthase/antagonists & inhibitors , Nitric Oxide Synthase/metabolism , Pregnancy , Protein Binding , Rats , Rats, Sprague-Dawley , Sulfonamides/pharmacology
8.
Syst Biol Reprod Med ; 55(5-6): 200-13, 2009 Dec.
Article in English | MEDLINE | ID: mdl-19938955

ABSTRACT

Increased oxidative DNA damage is observed in sperm devoid of contact with accessory sex gland (ASG) secretion. After fertilization, these sperm may produce abnormal embryos. In this study, we investigated the possibility that the pattern of DNA methylation and imprinted gene expression in these embryos may be perturbed. Epididymal sperm, uterine sperm, and embryonic day 13 (E13) embryos were collected from hamster and mouse. The extent of global DNA methylation was determined with an antibody against methylcytosine using an embryo DNA dot. The sperm and embryo Gtl2 promoter and H19 differential methylated region (DMR) were subject to bisulfite sequencing. Expression of their reciprocally activated genes Dlk1 and Igf2 was quantified by real-time PCR. Genome-wide DNA hypo-methylation in both hamster and mouse embryos sired by males without ASG was observed. The imprinting pattern of fetal mouse Gtl2 promoter and fetal hamster H19 DMR were also disrupted while the expression of Dlk1 and Igf2 was dysregulated in the hamster embryo. This study suggests that a lack of contact of sperm with the ASG secretion disrupts genome-wide DNA methylation and also affects the DNA methylation pattern of imprinted genes in embryos.


Subject(s)
DNA Methylation/drug effects , Genitalia, Male/metabolism , Genomic Imprinting/drug effects , Spermatozoa/physiology , Animals , Congenital Abnormalities/embryology , Cricetinae , Embryo, Mammalian/metabolism , Embryonic Development/genetics , Gene Expression Regulation, Developmental , Male , Mice , Prostatectomy , Proteins/genetics , RNA, Long Noncoding
9.
Theriogenology ; 71(9): 1367-80, 2009 Jun.
Article in English | MEDLINE | ID: mdl-19201017

ABSTRACT

Accessory sex gland (ASG) secretion is known to exert an effect on sperm that is heritable in hamster embryos. We hypothesized that ASG secretion changes the sperm epigenome, which in turn is propagated in sired embryos. To test our hypothesis, we produced male hamsters that were devoid of either all ASG (TX) or only the ventral lobe of the prostate gland (VPX). A sham-operated control group (SH) was also established. These males were mated with normal females; uterine sperm, fertilized oocytes, and pre-implantation embryos were harvested from the females after mating. Epididymal sperm were collected at the end of experiments. Immunofluorescent staining was performed on these harvested specimens using antibodies against 5-methylcytosine, Dnmt1, Dnmt3a, Dnmt3b, protamine 1, protamine 2, and aectyl-H4K5. Expression of Igf2 and Dlk1 were analyzed by real-time RT PCR and in situ hybridization. We demonstrated that the DNA methylation pattern changed dynamically in SH, TX, and VPX fertilized oocytes. In VPX and TX embryos, DNA demethylation was slower and remethylation was delayed when compared with SH embryos. In addition, Dnmt3b expression was also abnormal. When sperm from VPX and TX males were exposed to whole ASG secretion in vivo, the resulting embryos all methylated normally. Immunofluorescent staining revealed that there was no difference in protamine packaging of uterine sperm from VPX and TX males. The staining also showed a lower level of acetyl-H4K5 expression in the male pronuclei of TX produced embryos. Furthermore, the VPX and TX embryos also expressed higher levels Igf2, and Dlk1. We concluded that interactions between ASG and sperm affected: (1) histone acetylation in male pronuclei; (2) DNA methylation in fertilized oocytes; and (3) Igf2 and Dlk1 expression embryos.


Subject(s)
Embryonic Development , Epigenesis, Genetic/genetics , Genitalia, Male/metabolism , Insulin-Like Growth Factor II/genetics , Membrane Proteins/genetics , Mesocricetus/embryology , 5-Methylcytosine/analysis , Acetylation , Animals , Blastocyst/chemistry , Cricetinae , DNA (Cytosine-5-)-Methyltransferases , DNA Methylation , DNA Methyltransferase 3A , DNA Modification Methylases/analysis , Epigenesis, Genetic/physiology , Female , Fluorescent Antibody Technique , Gene Expression , Histones/chemistry , In Situ Hybridization , Intracellular Signaling Peptides and Proteins , Male , Mesocricetus/physiology , Pregnancy , Reverse Transcriptase Polymerase Chain Reaction , Spermatozoa/chemistry
10.
Int J Androl ; 32(6): 687-94, 2009 Dec.
Article in English | MEDLINE | ID: mdl-19076257

ABSTRACT

Leptin is a polypeptide hormone with important roles in reproduction. It has been detected in human seminal plasma as well as on human ejaculated spermatozoa. This study aimed at studying the possible role of leptin in regulating human sperm functions. Immunofluorescent staining was used to study the expression of leptin and its receptor. The correlation between the concentration of leptin and soluble leptin receptor (ObRs) in seminal plasma as measured by enzyme-linked immunosorbant assay and sperm motility parameters measured by computer-assisted sperm analysis (CASA) was determined. The effects of recombinant leptin on human sperm motility, capacitation and acrosome reaction as measured by chlortetracycline staining were also studied. Leptin immunoreactivity was demonstrated at the equatorial and neck regions of human spermatozoa, whereas that of ObRs was shown up on the tail. After Percoll separation, spermatozoa with high density had more intense leptin immunoreactivity compared with those with low density. No significant correlation was found between seminal plasma concentration of leptin/ObRs and sperm motility parameters. After incubation with recombinant human leptin for either 3 h or overnight, there was no change in all the CASA motility parameters determined and percentages of capacitated and acrosome-reacted spermatozoa. We concluded that leptin does not have a significant effect on motility and capacitation/acrosome reaction in human ejaculated mature spermatozoa. Its role in male reproduction is yet to be determined.


Subject(s)
Acrosome Reaction/drug effects , Leptin/metabolism , Leptin/pharmacology , Sperm Capacitation/drug effects , Sperm Motility/drug effects , Acrosome Reaction/physiology , Cell Count , Chlortetracycline/metabolism , Chlortetracycline/pharmacology , Humans , Male , Semen/metabolism , Sperm Motility/physiology , Spermatozoa/drug effects , Spermatozoa/metabolism , Spermatozoa/physiology
11.
Theriogenology ; 68(4): 654-62, 2007 Sep 01.
Article in English | MEDLINE | ID: mdl-17597198

ABSTRACT

The functional significance of male accessory sex glands (ASG) remains unclear. This study explored their importance in reproduction. In previous investigations, embryos sired by males with ASG either totally or partially removed had a shift in the cell cycle and delayed cleavage during preimplantation development, higher incidence of apoptosis, early oviductal-uterine transit, higher proportion of embryo degeneration, lower implantation rate, and ultimately reduced fertility and fecundity. Some pups were born alive; but would they be normal? We hypothesized that the first generation offspring (F1) could also bear undesirable traits. To test our hypothesis, we raised and studied these F1 pups from birth to 8 weeks. We monitored physical growth and assessed behaviour such as nest patch odor preference, acoustic startle response (ASR) and exploratory activity. We detected deviations from the norm in physical growth, a premature cessation of nest patch odor preferences, accelerated acoustic startle habituation and more frequent rearing when exposed to a novel environment. In terms of structure, we found one incidence of diphallus with duplicated urethra. We concluded that sperm lacking contact with ASG secretions gave rise to progeny with abnormal traits.


Subject(s)
Abnormalities, Multiple/etiology , Behavior, Animal/physiology , Genitalia, Male/physiology , Animals , Animals, Newborn , Birth Weight/physiology , Cricetinae , Embryonic Development/physiology , Female , Genitalia, Male/surgery , Male , Mesocricetus , Nesting Behavior/physiology , Odorants , Pregnancy , Random Allocation , Reflex, Startle
12.
J Endocrinol ; 181(2): 339-45, 2004 May.
Article in English | MEDLINE | ID: mdl-15128282

ABSTRACT

Adrenomedullin (AM) is a peptide involved in cardiovascular homeostasis and in inflammation. We examined its expression in a rat model of endotoxaemia. Male Sprague-Dawley rats received intraperitoneal injection of 5 or 10 mg/kg lipopolysaccharide (LPS), or saline as control. Rats were killed at 1, 3, 6, 12 and 24 h after injection. LPS at 5 mg/kg, but not saline, increased plasma AM significantly at 3 h. At 10 mg/kg, plasma AM was raised at 3, 6 and 12 h. Immunoreactive AM concentration in lung increased after 5 or 10 mg/kg LPS, but not saline. PreproAM mRNA level in lung was significantly increased at 3 and 6 h. In conclusion, endotoxin stimulates the expression of AM in the lungs and increases its circulatory concentration. AM may be involved in the systemic response to sepsis.


Subject(s)
Endotoxemia/metabolism , Lung/chemistry , Peptides/analysis , Adrenomedullin , Animals , Injections, Intraperitoneal , Lipopolysaccharides , Male , Models, Animal , Peptides/blood , Protein Precursors/genetics , RNA, Messenger/analysis , Rats , Rats, Sprague-Dawley , Time Factors
13.
Biol Reprod ; 69(3): 746-51, 2003 Sep.
Article in English | MEDLINE | ID: mdl-12724276

ABSTRACT

Abnormal spermatogenesis in men with Y-chromosome microdeletions suggests that genes important for spermatogenesis have been removed from these individuals. VCY2 is a testis-specific gene that locates in the most frequently deleted azoospermia factor c region in the Y chromosome. We have raised an antiserum to VCY2 and used it to characterize the localization of VCY2 in human testis. Using Western blot analysis, the affinity-purified polyclonal VCY2 antibody gave a single specific band of approximately 14 kDa in size, corresponding to the expected size of VCY2 in all the collected human testicular biopsy specimens with normal spermatogenesis. Immunohistochemical analyses showed that VCY2 localized to the nuclei of spermatogonia, spermatocytes, and round spermatids, except elongated spermatids. At the ultrastructural level, VCY2 expression was found in the nucleus of human ejaculated spermatozoa. To determine the possible relationship of VCY2 with the pathogenesis of male infertility, we examined a group of infertile men with and without Y-chromosome microdeletions and with known testicular pathology using VCY2 antibody. VCY2 was weakly expressed at the spermatogonia and immunonegative in spermatocytes and round spermatids in testicular biopsy specimens with maturation arrest or hypospermatogenesis. The specific localization of the protein in germ cell nuclei indicates that VCY2 is likely to function in male germ cell development. The impaired expression of VCY2 in infertile men suggests its involvement in the pathogenesis of male infertility.


Subject(s)
Chromosome Deletion , Chromosomes, Human, Y/metabolism , Infertility, Male/genetics , Infertility, Male/metabolism , Proteins/metabolism , Spermatozoa/metabolism , Testis/metabolism , Adult , Biopsy , Blotting, Western , Cell Nucleus , Chromosomes, Human, Y/genetics , Chromosomes, Human, Y/ultrastructure , Humans , Immunohistochemistry , Infertility, Male/pathology , Male , Proteins/genetics , RNA, Messenger/analysis , Spermatogenesis/physiology , Spermatozoa/pathology , Spermatozoa/ultrastructure , Testis/pathology
14.
Cell Tissue Res ; 311(3): 417-25, 2003 Mar.
Article in English | MEDLINE | ID: mdl-12658449

ABSTRACT

Galactosemia is a genetic disease with deficiency of galactose-1-uridyltransferase, resulting in the accumulation of galactose or galactose-1-phosphate in the blood and tissues. Rats were fed with normal rat chow and with a high-galactose diet for 4 weeks to give control and galactosemic groups, and their ovarian function was studied. The two groups of rats were injected with pregnant mare's serum gonadotrophin (PMSG) and were killed at different time points after human chorionic gonadotrophin (hCG) injection. The number of oocytes ovulated in the controls was significantly higher than in the galactosemic group. Morphometric studies of the ovaries also showed a higher number of corpora lutea in the controls. Western blot analysis of granulosa cells showed that the overall expressions of Fas and FasL were lower in the control group and their expressions of inhibitor of apoptosis proteins (IAPs) were higher than in the galactosemic group, especially at 8 h post hCG injection. TDT-mediated dUTP-biotin nick end-labeling (TUNEL) and immunohistochemical staining of ovarian sections with Ki-67 and IAPs showed more apoptotic granulosa cells in the galactosemic group and the expressions of IAPs in granulosa cells also confirmed the result of the Western blot. These findings support our hypothesis that ovarian dysfunction in galactosemic rats is due to increased apoptosis in granulosa cells of maturing follicles.


Subject(s)
Apoptosis/physiology , Galactosemias/complications , Granulosa Cells/metabolism , Ovarian Diseases/etiology , Proteins/metabolism , Animals , Baculoviral IAP Repeat-Containing 3 Protein , Cell Survival/physiology , Chorionic Gonadotropin/pharmacology , Disease Models, Animal , Fas Ligand Protein , Female , Food, Formulated/adverse effects , Galactose/adverse effects , Galactose/metabolism , Galactosemias/metabolism , Galactosemias/pathology , Gonadotropins, Equine/pharmacology , Granulosa Cells/pathology , Inhibitor of Apoptosis Proteins , Membrane Glycoproteins/metabolism , Ovarian Diseases/metabolism , Ovarian Diseases/pathology , Rats , Rats, Sprague-Dawley , fas Receptor/metabolism
15.
Anat Embryol (Berl) ; 206(3): 203-13, 2003 Feb.
Article in English | MEDLINE | ID: mdl-12592572

ABSTRACT

To account for reproductive failure induced by surgical deletion of paternal accessory sex glands in the golden hamster in vivo, we studied expression of vegf, FLT-1 (VEGF-R1), FLK-1 (VEGF-R2), MMP and TGF-beta in endometrium of the dam and sired embryos during 5-7 days post coitum by immunohistochemistry, in situ hybridisation, semiquantitative RT-PCR and enzyme-linked immunosorbent assay. Spatiotemporal pattern of vegf expression in the control animals was similar to that reported for intact animals by our group. Removal of paternal ampullary glands did not disturb the normal expression pattern. Removal of ventral prostate glands alone or all accessory sex glands was associated with reduction of vegf transcripts and protein levels in both the embryo and endometrium. FLT-1, FLK-1 and MMP-2 were also reduced. MMP-1 was not changed whereas TGF-beta1 expression was enhanced. There was no expression in endometrium in between implantation sites. Thus the implanted embryos had a trophic effect on growth factor production by the endometrium, and the levels of expression were determined by viability and structural integrity of the conceptus. Based on these findings we concluded that incompetent embryos sired by males without the ventral prostate gland or all accessory sex glands reduced the potential of the uterus to support pregnancy. A negative cycle of events was thus set up and eventually led to premature termination of pregnancies.


Subject(s)
Embryo Implantation/physiology , Embryo, Mammalian/metabolism , Embryo, Mammalian/physiopathology , Endometrium/growth & development , Genitalia, Male/metabolism , Growth Substances/metabolism , Maternal-Fetal Exchange/physiology , Animals , Cricetinae , Endometrium/cytology , Endometrium/metabolism , Female , Genitalia, Male/injuries , Immunohistochemistry , Lectins , Male , Matrix Metalloproteinases/metabolism , Pregnancy , Prostate/metabolism , Seminal Vesicles/metabolism , Transforming Growth Factor beta/metabolism , Vas Deferens/metabolism , Vascular Endothelial Growth Factor Receptor-1/metabolism , Vascular Endothelial Growth Factor Receptor-2/metabolism
16.
Int J Gynecol Pathol ; 22(1): 63-70, 2003 Jan.
Article in English | MEDLINE | ID: mdl-12496700

ABSTRACT

E-cadherin and beta-catenin are cell-cell adhesion molecules, which are thought to play an important role in trophoblastic differentiation and remodelling during gestation. Their expression may be altered in pathological conditions with trophoblastic invasion. In this study, we used immunohistochemical methods to study the pattern of expression of E-cadherin and beta-catenin in villous trophoblastic tissue in normal and pathological pregnancies. In villous trophoblastic tissue, E-cadherin had a membranous distribution, whereas beta-catenin had a mixed-membranous and granular cytoplasmic distribution. The levels of expression of E-cadherin and beta-catenin correlated with each other. From first to third trimesters, the expression of both E-cadherin and beta-catenin showed a decreasing trend. In preeclampsia, there was an up-regulation of E-cadherin and beta-catenin expression. In placenta accreta, the level of expression of both did not differ from that in normal third-trimester placenta. In gestational trophoblastic diseases, there was a general trend of down-regulation of both E-cadherin and beta-catenin. Altered expression of E-cadherin and beta-catenin may play a role in the development of normal and pathological placentas.


Subject(s)
Cadherins/biosynthesis , Cytoskeletal Proteins/biosynthesis , Placenta Accreta/metabolism , Pre-Eclampsia/metabolism , Trans-Activators/biosynthesis , Trophoblastic Neoplasms/metabolism , Trophoblasts/metabolism , Uterine Neoplasms/metabolism , Female , Humans , Immunohistochemistry , Placenta Accreta/pathology , Pre-Eclampsia/pathology , Pregnancy , Trophoblastic Neoplasms/pathology , Trophoblasts/pathology , Uterine Neoplasms/pathology , beta Catenin
17.
Reproduction ; 124(4): 491-9, 2002 Oct.
Article in English | MEDLINE | ID: mdl-12361467

ABSTRACT

Reactive oxygen species scavengers present in male accessory sex gland secretions might afford antioxidant protection to sperm DNA. This study was conducted to determine whether accessory sex gland secretions protect the genome and function of spermatozoa against oxidative damage in the uterus. Male golden hamsters were divided into four experimental groups: (i) all accessory sex glands removed; (ii) ampullary glands removed; (iii) ventral prostate gland removed and (iv) sham-operated controls. Ejaculated spermatozoa recovered from uteri 15-30 min after mating with experimental males and caput and cauda epididymal spermatozoa obtained from intact males were incubated in 0-20 mmol NADPH l(-1) for 2 h. These spermatozoa and untreated uterine spermatozoa were processed for two types of comet assay (single cell gel electrophoresis): alkaline comet assay (pH > 13) which revealed single-strand DNA breakage and neutral comet assay (pH 9) which revealed double-strand DNA breakage. In comparison with the sham-operated controls, spermatozoa that had not been exposed to accessory sex gland secretions had a higher incidence and more extensive single-strand DNA damage with increasing concentrations of NADPH. Spermatozoa from hamsters without ampullary glands and from hamsters without the ventral prostate glands were similar to those of the control group. After incubation with NADPH, the capacity of spermatozoa from hamsters without accessory glands and from sham-operated controls to fuse with oocytes in vitro was reduced. However, only hamsters without accessory glands showed a negative correlation between single-strand DNA damage and sperm-oocyte fusion. Cauda epididymal spermatozoa were less susceptible to NADPH treatment compared with caput epididymal spermatozoa. The results of the present study showed that male accessory sex gland secretions can preserve the integrity of the sperm genome.


Subject(s)
DNA Damage , Genitalia, Male/metabolism , Oxidative Stress , Spermatozoa/physiology , Animals , Biological Factors/physiology , Cricetinae , Dose-Response Relationship, Drug , Epididymis , Female , Male , Mesocricetus , NADP/pharmacology , Sperm-Ovum Interactions/physiology , Spermatozoa/drug effects , Uterus
18.
Ultrasound Obstet Gynecol ; 19(5): 484-9, 2002 May.
Article in English | MEDLINE | ID: mdl-11982983

ABSTRACT

OBJECTIVES: To investigate the variation of endometrial responsiveness between cycles within the same women undergoing assisted reproduction. METHODS: The sonographic endometrial thickness in ovarian stimulation cycles was compared with that of subsequent natural cycles. One hundred and thirty-six ovarian stimulation cycles of in-vitro fertilization and embryo transfer were evaluated. Women who did not conceive in in-vitro fertilization cycles were subsequently seen in natural cycles (n = 97) or the next in-vitro fertilization cycle (n = 39). Based on a receiver-operating characteristics (ROC) curve using endometrial thickness to predict pregnancy, the first in-vitro fertilization cycles were classified according to the endometrial thickness as optimal (> 8 mm) in 98 cycles, or suboptimal (< or = 8 mm) in 29 cycles. Similarly, spontaneous cycles were classified as suboptimal (< or = 7 mm) in 28 cycles and optimal (> 7 mm) in 69 cycles. RESULTS: The pregnancy rates were significantly lower (P < 0.05; Fisher's Exact test) in the suboptimal group in both the in-vitro fertilization and frozen embryo transfer cycles. There was a strong correlation (r2 = 0.745) and a significant difference (P < 0.001; Wilcoxon signed rank sum test) between the endometrial thickness of stimulation and natural cycles. CONCLUSION: It is possible to predict the occurrence of optimal or suboptimal endometrial response in natural cycles of women, after evaluation in stimulated cycles, with a high degree of reliability. Risk of implantation failure can be identified before subsequent treatment cycles and adjuvant therapeutic strategies may be planned to improve the endometrial response before embryo transfer.


Subject(s)
Embryo Transfer , Endometrium/diagnostic imaging , Menstrual Cycle/physiology , Pregnancy/statistics & numerical data , Adult , Cohort Studies , Endometrium/drug effects , Female , Fertilization in Vitro , Humans , Infertility, Female/therapy , Ovulation Induction/methods , Probability , Sampling Studies , Sensitivity and Specificity , Statistics, Nonparametric , Ultrasonography, Prenatal
19.
Hum Reprod ; 16(10): 2114-7, 2001 Oct.
Article in English | MEDLINE | ID: mdl-11574501

ABSTRACT

BACKGROUND: Gonadotrophins are used in many assisted reproduction units to achieve a better success rate by increasing the number of replaced embryos. However, high oestradiol concentrations are associated with altered physiological functions and its complications. We investigated whether high oestradiol concentrations (> or =20 000 pmol/l) after ovarian stimulation in infertile women would affect the uterine haemodynamics at the time of embryo transfer. METHODS: Colour Doppler indices of utero-ovarian arteries and endometrial colour signals were measured. Fifty-eight women undergoing ovarian stimulation for IVF were classified according to serum oestradiol concentrations on the day of human chorionic gonadotrophin injection into moderate responders (oestradiol <20 000 pmol/l; n = 39) and high responders (oestradiol > or =20 000 pmol/l; n = 19). RESULTS: Haemodynamic parameters were significantly lower in high responders; the uterine arterial pulsatility index (PI) and resistance index (RI) were (median; range) 1.87 (0.84-2.82) and 0.79 (0.57-0.90) respectively; ovarian artery PI was 0.57 (0.40-1.12) and RI was 0.43 (0.33-0.64). In moderate responders the uterine PI and RI were 2.63 (1.46-5.92) and 0.88 (0.77-1.10) respectively. Ovarian PI was 0.81 (0.32-3.72) and RI was 0.55 (0.23-0.97). The number of women showing endometrial colour signals was significantly lower in high responders (63%) than in moderate responders (92%) (P < 0.05). A further increase in oestradiol (> or =25 000 pmol/l; n = 8) showed significantly (P = 0.03) fewer endometrial colour signals [1.5 (0-8)] compared with moderate responders [4 (0-14)]. CONCLUSION: Despite low uterine PI and RI, the endometrial blood flow in high responders appears to be impaired. This may contribute to the decline in implantation efficiency noted in high responders.


Subject(s)
Estradiol/blood , Ovary/blood supply , Ovulation Induction , Ultrasonography, Doppler, Color , Uterus/blood supply , Adult , Arteries/physiopathology , Endometrium/blood supply , Female , Hemodynamics , Humans , Osmolar Concentration , Prospective Studies , Pulsatile Flow , Regional Blood Flow , Vascular Resistance
20.
Anat Embryol (Berl) ; 204(2): 117-22, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11556527

ABSTRACT

The effects of total removal of paternal accessory sex glands (TX) on preimplantation embryonic development was studied in the golden hamster model. Cell numbers of the two groups of embryos did not differ up to 60 h p.c., but at 66 and 70 h p.c., each TX embryo has 2 and 3 cells less respectively (P<0.05, TX vs SH). At 70 h p.c., 46.6+/-4.4 of the TX embryos blastomeres were labelled with the terminal deoxynucleotide transferase - mediated dUTP-nickend-labelling technique, compared with 31.5+/-2.1 in the SH group (P<0.01, TX vs SH). No difference was found in the SDS-PAGE profiles of two-cell embryos from the two groups. An extra band corresponding to 136.5 kDa was consistently found in the four-cell TX embryos. The nascent proteins profiles of four-cell embryos from the two groups were similar. As the embryos progressed from two to four cells, the protein content decreased by 16% in the SH embryos (P<0.05) and 7% in the TX embryos. These observations suggest that total ablation of paternal accessory sex glands could result in developmental aberrations from the two-cell to morula stages and a higher incidence of apoptosis at 70 h p.c.


Subject(s)
Blastocyst/physiology , Embryonic and Fetal Development/physiology , Genitalia, Male/physiology , Genitalia, Male/surgery , Animals , Apoptosis , Blastocyst/chemistry , Blastocyst/cytology , Cell Count , Cricetinae , Female , Male , Mesocricetus , Morula/chemistry , Morula/cytology , Morula/physiology , Pregnancy , Proteins/analysis
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