Endocrine Abstracts

Objective: In the marmoset (Callithrix jacchus) the LH is functionally replaced by the chorionic gonadotropin (CG). However, disparate to the human LH/hCG system, marmoset CG is expressed in both, the pituitary and in the placenta. Previously, we could show the presence of a tissue-specific promoter system in the marmoset. Alternative promoters, as well as different first exons, either a pituitary or a novel placenta specific one, are being employed to direct tissue spe...

Introduction: FSH is a key player in reproductive functions, the expression of its unique subunit FSHB is regulated by the FSHB promoter. Recently, a single nucleotide polymorphism (SNP) at a highly conserved position in the FSHB promoter (rs10835638; −211G>T) has been found to be associated with decreased serum FSH levels in men and with male infertility. Because to date no information is available on possible endocrine consequences of this SNP in women, we conducte...

Testosterone is the hormone that turns males into men and a lack of testosterone, whether of primary or secondary origin, causes hypogonadism characterized by lack of pubertal development or loss of maleness. It was generally assumed that in a man with a normal androgen receptor (AR) androgenicity is regulated by testosterone serum concentrations, slightly modified by SHBG. Only recently it became evident that variations in the AR gene influence testosterone action. Modulation...

Background: The LHR is a crucial mediator for normal sexual development and fertility. In the marmoset monkey (Callithrix jacchus), LHR type II, lacking exon 10, is the native receptor type. In addition to the testis, the LHR is expressed in the adrenal gland where its function remains unknown.Aim: To characterise marmoset LHR expression at different stages of puberty in the testis and adrenal gland and examine different splice variants in the tes...

Follicle-stimulating hormone (FSH) is essential for primate reproduction, acting via the FSH-receptor (FSHR) which is expressed in Sertoli and granulosa cells only. Despite its highly specific expression pattern, knowledge of the FSHR promoter and transcriptional regulation is still very limited. To gain insights into the regulatory elements controlling FSHR expression we characterized the core promoter activity of all important primate lineages including human. We isolated DN...

Klinefelter syndrome (47,XXY; KS) is a very common chromosomal disorder, affecting 1:500 men and leading to hypergonadotropic hypogonadism as well as an increased incidence of metabolic syndrome. However, our knowledge on the functional role of the supernumerary X chromosome itself and to which extent its origin contributes to the observed pathophysiology is still very limited. Recently we started the EXAKT (Epigenetics, X-Chromosomal features and clinical Applications in Klin...

Introduction: Klinefelter Syndrome (KS; 47,XXY) is the most common sex chromosome disorder in men, characterized by hypergonadotropic hypogonadism. EXAKT (Epigenetics, X-chromosomal features and clinical Applications in Klinefelter syndrome Trial) is a Muenster-based prospective project involving Klinefelter patients and their parents assessing a wide area of cardiovascular, inflammatory and metabolic factors as well as a broad range of genetic and epigenetic investigations es...

Activation of the human LH/CG receptor (LH/CGR) by lutropin (LH) and choriogonadotropin (CG) is essential in the human reproduction. Deletion of the Exon10 (LH/CGR-delExon10) resulting in a lack of 27 amino acids within the extracellular hinge-region of LH/CGR causes Leydig cell hypoplasia type II. To clarify why this deletion impairs LH but not CG action, we investigated the molecular determinants of LH/CGR activation elucidating the different behaviour of both hormones.<...

Background and Aim: Klinefelter syndrome (47,XXY; KS) is a very common chromosomal disorder, affecting 1:600 men. Klinefelter men have been described to exhibit clinically relevant metabolic patterns related to a pro-inflammatory status, resulting in a high prevalence of insulin resistance and cardiovascular impairment. Testosterone deficiency in form of primary hypogonadism is a common feature in these men.EXAKT (epigenetics, X-chromosomal features and ...

Introduction: Recently, a single nucleotide polymorphism (SNP) in the FSH (FSH)-β gene (FSHB −211G>T, rs10835638) that leads to reduced mRNA transcription was associated with serum FSH levels in an Estonian cohort of young men (Grigorova et al., Hum Reprod 2008). Further investigations showed an increased frequency of the T-allele in patients with oligozoospermia compared to men with normozoospermia (Grigorova et al., JCEM 2010). Another Bal...