Endocrine Abstracts

Activation of the G-protein coupled receptor GPR54 (AXOR12, OT7T175) by peptide ligands (kisspeptins) encoded by the Kiss-1gene is central to acquisition of reproductive competency in mammals. Administration of exogenous kisspeptins stimulates GnRH release from hypothalamic neurons in several species including humans. To confirm that kisspeptins are the natural agonist of GPR54 in vivo and to determine if these ligands have additional physiological functions, we ...

Leukemia inhibitory factor (LIF), a pleiotropic cytokine of the interleukine-6 superfamily, is involved in several functions including the control of reproduction at the embrionic-endometrial interface and the regulation of energy homeostasis. LIF activates a cell-surface receptor complex (LIF-Rs) composed of one ligand-specific low affinity LIF receptor β (LIFRβ) subunit and the gp130 subunit. Since little is known about the involvement of LIF in the modulation of t...

The molecular mechanisms underlying the reawakening of hypothalamic GnRH neurons at puberty remain to be elucidated. Recently, the G protein-coupled receptor 54 (GPR54) and its endogenous ligand kisspeptin, encoded by the KISS1 gene, have been involved. In fact, GPR54 mutations cause idiopathic hypogonadotropic hypogonadism in human and mice. We used the previously characterized primary culture of human fetal olfactory GnRH-secreting neurons, FNC-B4, to study in vitro t...

EGFR ligands, a family of seven related peptide growth factors, are emerging as key factors regulating different aspects of female reproduction including oocyte maturation and ovulation, and implantation. Betacellulin (BTC) is a rather neglected EGFR ligand whose biological activities have been mostly associated with the endocrine pancreas. During the routine breeding of recently established BTC transgenic mouse lines (Schneider et al., Endocrinology 146, 5237–5246, 2005)...

Recent studies demonstrate an essential role of the EGF network in propagating the LH signal within ovarian preovulatory follicles. However, the molecular bases for the integration are poorly characterized. Here, we propose that the early LH signal leading to ovulation is amplified through activation of the EGF network.For this study, preovulatory follicles from euthanized gonadotropin-primed mice were isolated and cultured with or without recombinant LH...

Introduction and aim: Polycystic Ovary Syndrome (PCOS) is a common disorder associated with a wide range of endocrine and metabolic abnormalities. Obesity is present in about 45–50% of PCOS women. Increased cardiovascular risk factors and evidence of subclinical cardiovascular disease (CVD) have been reported in PCOS. The aim of the present study was to evaluate whether visceral fat amount may be considered as predictor for early CVD in PCOS women.P...

Background: The prevalence of the metabolic syndrome (MS) is notably higher in patients with PCOS than in the general population. Presumably, this prevalence increases as a function of age but the subgroups of patients less than 20 yr. old studied so far are small.Design: In order to further document this issue, we have selected for this study 498 patients with PCOS aged 12.5–38 yr (Rotterdam definition) and 188 control women aged 15.5–38.5 yr,...