Simon C. Riley

Culture of Bovine Preantral Follicles in a Serum-Free System: Markers for Assessment of Growth and Development

Abstract Satisfactory development of bovine follicles in vitro remains elusive. This study used a serum-free system to evaluate the effects of insulin-like growth factor-1 (IGF-1) on bovine preantral follicles in culture and to identify the activity of gelatinase matrix metalloproteinases (MMPs) and their endogenous inhibitors (TIMPs) in vitro to assess their potential as markers of development. Preantral follicles were cultured for 6 days in serum-free medium containing insulin and IGF-1 (10 ng/ml). No difference was observed in follicular growth, health, or antrum formation between IGF-1-treated follicles and controls. However, IGF-1 had a negative effect (P < 0.01) on oocyte size and granulosa cell proliferation. When MMP-9 was secreted, the probability of follicles having healthy granulosa or theca cells at the end of the culture period was 0.85 and 0.60, respectively. If TIMP-1 was released, the probability of follicles having healthy somatic cells was 0.79. When TIMP-2 was detected, the probability of granulosa and theca cell health was 0.78 and 0.67, respectively. These results demonstrate no positive effects of IGF-1 on bovine follicles in this system. Furthermore, MMP-9 and TIMPs are related to follicular health and, therefore, can be used as markers of follicular development.

2. Corticotrophin-releasing hormone production by the placenta and fetal membranes

Maturation of the fetal hypothalamic-pituitary-axis may be an important factor in the stimulation of the onset of parturition. Recent studies have found that corticotrophin-releasing hormone (CRH), the hypothalamic component of this axis is also present in the placenta and the fetal membranes. We review the evidence demonstrating that glucocorticoids stimulate the production of CRH by these tissues towards term, and this is manifest by increases in CRH concentrations in maternal and fetal plasma and in placental extracts, and by increased abundance of CRH mRNA in the placenta. We discuss how CRH secretion by the placenta and fetal membranes is controlled. We hypothesize that CRH may be an important signal in initiating of the onset and maintenance of term labour and may also be a factor in the etiology of premature labour, through stimulation of the fetal HPA axis, and through paracrine/autocrine interactions within the placenta, fetal membranes and decidua.

Cytokines and the regulation of apoptosis in reproductive tissues : A Review

PROBLEM: To determine the role of apoptosis‐regulating genes bax and bcl‐2 in reproduction.

Maternal serum activin, inhibin, human chorionic gonadotrophin and α-fetoprotein as second trimester predictors of pre-eclampsia

Objective To compare the serum levels of human chorionic gonadotrophin (hCG), α‐fetoprotein, activin A, inhibin A and inhibin isoforms containing pro and αC in the second trimester serum of women who subsequently developed hypertensive disorders of pregnancy with those who remained normotensive throughout pregnancy.

Elafin (SKALP/Trappin-2/proteinase inhibitor-3) Is Produced by the Cervix in Pregnancy and Cervicovaginal Levels Are Diminished in Bacterial Vaginosis

Objectives. To examine cervicovaginal elafin production in pregnancy and determine its relationship in bacterial vaginosis. Study Design. Samples of cervicovaginal secretions were collected from women with uncomplicated singleton pregnancies (n = 112) below 20 weeks gestation. Bacterial flora was assessed using Nugent’s criteria, and levels of elafin were measured by enzyme-linked immunosorbent serologic assay (ELISA). Elafin expression in the cervix was also examined by immunohistochemistry. In vitro expression of elafin was examined using cervix and vaginal cell lines. Results. Elafin is expressed in the cervical glandular epithelium. Elafin was found in all 112 samples of cervicovaginal secretions and levels were diminished in women with bacterial vaginosis (P < .05). Interleukin 1β (IL-1β) stimulated elafin expression in cells derived from the endocervix, but not in those derived from the vaginal epithelium. Conclusions. Elafin is a component of cervicovaginal secretions in pregnancy, and levels are diminished in bacterial vaginosis. It may be an important component of innate immunity in the lower genital tract.

Decreased serum levels of kisspeptin in early pregnancy are associated with intra-uterine growth restriction and pre-eclampsia

To investigate whether pregnancies with development of subsequent pre‐eclampsia and intra‐uterine growth restriction are associated with altered levels of kisspeptin in maternal serum in the second trimester.

G-1-Activated Membrane Estrogen Receptors Mediate Increased Contractility of the Human Myometrium

Estrogens are key mediators of increased uterine contractility at labor. We sought to determine whether membrane-associated estrogen receptors, such as the recently described seven-transmembrane receptor G protein-coupled receptor 30 (GPR30), mediated some of this effect. Using human myometrium obtained at term cesarean section before or after the onset of labor, we demonstrated the presence of GPR30 mRNA and protein using quantitative RT-PCR and Western blotting. GPR30 receptor was localized to the cell membrane and often colocalized with calveolin-1. Using the specific estrogen membrane receptor agonist G-1 and myometrial explants, we showed that membrane receptor activation led to phosphorylation of MAPK and the actin-modifying small heat shock protein 27. Using myometrial strips incubated with G-1 or vehicle we demonstrated that estrogen membrane receptor activation increased the myometrial contractile response to oxytocin. These data suggest that activation of the plasma membrane estrogen receptor GPR30 likely participates in the physiology of the human myometrium during pregnancy and identifies it as a potential target to modify uterine activity.

Concentrations of inhibin, progesterone and oestradiol in fluid from dominant and subordinate follicles from mares during spring transition and the breeding season

Dominant and subordinate follicles were collected from mares on the day after the dominant follicle reached 30 mm in diameter, to investigate regulation of folliculogenesis during spring transition and the breeding season. Concentrations of oestradiol-17beta, progesterone and inhibin A, but not inhibin isoforms with pro- and alpha C-immunoreactivity, were significantly higher in preovulatory follicles than in dominant anovulatory transitional follicles. Steroidogenic activity was regained gradually in the dominant follicles of successive anovulatory waves through spring transition. The dominant follicles, during both spring transition and cyclicity, contained higher concentrations of oestradiol, progesterone and inhibin A, but not inhibin pro- and alpha C-isoforms, than subordinate follicles. The results indicate that high follicular levels of oestradiol, progesterone and inhibin A are associated with continued follicle growth and ovulation. The low concentrations of oestradiol and progesterone in transitional follicles indicate that the deficiency in steroidogenesis exists early in the steroidogenic pathway. The similarity in patterns of follicular hormones in spring transition and during cyclicity strongly suggests that the mechanism of dominance is the same in both types of follicle.

Regulation of interleukin 8 production in the term human placenta during labor and by antigestagens

OBJECTIVE Our purpose was to assess the effects of labor and antigestagens on production of interleukin 8 by the term human placenta and to localize interleukin 8 in first- and third- trimester placentas. STUDY DESIGN The study was conducted by the Department of Obstetrics and Gynaecology of the University of Edinburgh. Five placentas were collected after spontaneous and cesarean deliveries. Explants were cultured in the presence of mifepristone, lilopristone, or onapristone. The production of interleukin 8 was determined by specific radioimmunoassay, and the immunolocalization of interleukin 8 was determined in sections of first- and third-trimester placentas. RESULTS All explants produced interleukin 8. Production was significantly increased (P < .05) after spontaneous delivery. In placentas delivered spontaneously, onapristone significantly increased production of interleukin 8 (P < .05), whereas in those from cesarean deliveries lilopristone caused a significant increase in production (P < .05). In the third-trimester placenta interleukin 8 was localized in the perivascular area of fetal vessels. In first-trimester villi it was peripherally located in syncytiotrophoblast. CONCLUSION The human placenta at term is capable of producing interleukin 8, which is localized around the perivascular area of the villi. Production is increased after spontaneous labor and to varying degrees by the antigestagens studied. Interleukin 8 may have a role in the onset of parturition by recruiting and activating neutrophils at the placental site.

Serum inhibin, activin and follistatin in postmenopausal women with epithelial ovarian carcinoma

Objective To investigate the role of serum inhibin A, inhibin pro‐αC immunoreactivity, activin A, and follistatin in postmenopausal women with epithelial ovarian cancer.