Endocrine Abstracts

Introduction: The developmental stages of the ovarian follicle are characterized by changes of gonadotropin and steroid hormone receptor expression and their potential interactions on the surface of granulosa cells. In this study in vitro, we aim to evaluate whether the co-existing follicle-stimulating hormone receptor (FSHR) and G protein-coupled estrogen receptor (GPER) form heteromers, which may play role in selecting the dominant ovarian follicle.<p class="abs...

Pituitary luteinizing hormone (LH) and placental human choriogonadotropin (hCG) are two heterodimeric glycoprotein hormones regulating reproduction. They bind the same receptor (LHCGR) expressed in gonadal cells, activating hormone-specific G protein- and β-arrestins-dependent signaling cascades, before LHCGR internalization. LH induces preferential proliferative signals, while hCG activates mainly the steroidogenic pathway, reflecting their physiological roles. In this s...

Background: Environmental rhythmicity seems able to affect the hypothalamic-pituitary-gonadal axis in animals to achieve reproductive advantages. However, conflicting results were obtained when assessing the environmental-dependent rhythmicity on reproductive hormone secretion in humans.Aim of the study: This study was designed to evaluate seasonal fluctuations of the main hormones involved in the hypothalamic-pituitary-gonadal axis in men, using a big d...

Objective: Aromatase, the key enzyme involved in estrogen synthesis, is expressed in a variety of cells, including peripheral blood leukocytes (PBLs), and tissues. The systematic study of aromatase expression and activity in different tissues in the human and other primates, however, is difficult and still missing. Although is not really known, aromatase expression in PBLs could be used as parameter of aromatase expression/activity making PBLs a potential alternative for other...

Objective: Aromatase, the key enzyme involved in estrogen synthesis, is expressed in a variety of cells and tissues including human peripheral blood leukocytes (PBLs). The present study was designed to evaluate PBL aromatase gene expression in male and female elderly subjects compared to young male controls.Design: CYP19A1 mRNA and protein were measured in PBLs obtained from young men (n=13) aged < 35 years, postmenopausal women (n</...

Introduction: Several numerical chromosome abberations are known in men. Of those the karyotype XXY (Klinefelter syndrome KS) is the most common chromosomal disorder with a prevalence of about one in 500 live-born males. KS is associated with hypogonadism and is suspected to cause variable physical and cognitive abnormalities. As a supernumerary X chromosome is also associated with infertility, sound animal models for KS are difficult to obtain.Methods: ...

Sertoli cell-only syndrome (SCOS) is characterized by a lack of germ cells and thickened seminiferous tubule walls and is a frequent finding among men with non-obstructive azoospermia. Spermatogenesis is dependent upon the function and number of Sertoli cells (SC) to support the developing germ cells. Klinefelter syndrome is the most frequent genetic cause of SCOS and presents histological features in common with idiopathic SCOS. Aim of this study was to analyze the relationsh...

Objective: Anti-Müllerian hormone (AMH) has recently been evaluated as a marker for follicle reserve and as a new marker for ovarian function in women. In the male, it is produced in Sertoli cells (SC) in the testis. We evaluated serum levels of AMH as a marker of SC function and male fertility by comparing normo- and oligozoospermic men.Materials and methods: Serum levels of AMH were determined by enzyme immunoassay in two groups of men with normal...

Background: During spermatogenesis protamines replace histones in sperm head. Haploinsufficiency of the protamine (PRM) 1 or PRM2 gene causes infertility in mice. A mutation in PRM1 was associated with increased abnormal sperm morphology in infertile men1. We assessed the frequency of mutations and SNPs in the PRM1 and PRM2 gene in infertile patiens with normal sperm concentration and reduced morphology, a phenotype similar to that...

Introduction: A primate-specific luteinizing hormone (LH) receptor (LHCGR)-variant was suspected to discriminate between maternal choriogonadotropin (hCG)- and fetal LH-functioning. It is the so-called “LHCGRex6A”, truncated, intracellular receptor isoform produced by alternative cryptic exon stop-codons located between the 6th-7th out of 11 exons. Its function is unknown, although pseudohermaphroditism and 46-XY female-like phenotype were associated with LHCGRex...