Endocrine Abstracts

Central obesity is strongly associated with insulin resistance and chronic sub-clinical inflammation, which is implicated in the development of type 2 diabetes (T2DM). However, the mechanisms underlying this link remain unclear. Recently JNK, a mitogen activated protein kinase (MAPK), has been implicated in obesity and insulin resistance by interfering with insulin action. Studies in rodent models show that phosphorylated JNK-1 is elevated in obesity, whilst the absence of JNK...

Introduction: Sex hormone-binding globulin (SHBG) regulates the bioavailability of sex steroid hormones, which in turn regulate reproductive function. The potential association of SHBG gene polymorphisms with the age at menopause has not been examined.Objective: The present study aimed to assess the possible relationship between the pentanucleotide (TAAAA)n repeat polymorphism in the promoter of the SHBG gene and the age at menopause in a Greek fe...

Background: Osteocalcin (OC) is a bone-specific protein produced primarily by osteoblasts during bone formation. The OC concentration is used to assess fracture risk and monitor treatment of osteoporosis and other disorders of bone metabolism. To adequately interpret the OC concentration, it is necessary to calculate reference ranges from a healthy reference population, adapted to a specific laboratory method.Methods: We established a healthy reference p...

With the cloning of the gene encoding pro-opiomelanocortin (POMC) it became apparent that several other peptides distinct from ACTH would be co-secreted from the anterior pituitary into the circulation. This begged the question as to whether these peptides have any biological actions on the adrenal, or to that matter any other tissue. Over the past two decades it has become apparent that the N-terminal fragment known as pro-gamma-MSH plays a role in adrenal physiology.<p c...

Aim: Somatic growth results from the generation of new support and connective tissue. Since collagen is the major protein constituent of connective tissue, its synthesis must be a prerequisite for the normal growth. The aim of the study was to determine age-related reference intervals for P3NP, a collagen – formation marker in a group of normal height prepubertal children and to compare to IGF1 levels.Subjects: Forty-three prepubertal children, male...

In respect to growth, the adrenal is a dynamic organ that requires constant stimulation from peptides derived from the ACTH precursor pro-opiomelanocortin (POMC) to maintain its tonic state. Previous studies have suggested that the adrenal mitogen resides in the N-terminus of pro-gamma-MSH, which upon cleavage results in the generation of shorter mitogenic peptides not containing the gamma-MSH sequence. This hypothesis has recently been substantiated by our characterisation of...

Introduction: Using discriminant analysis, a method based on two growth hormone (GH) dependent markers, insulin-like growth factor-I (IGF-I) and pro-collagen type III N-terminal peptide (P-III-P) has been devised to detect exogenously administered GH. It is believed that GH is a popular substance of abuse amongst adolescent athletes. As previous studies on the detection of GH abuse involved predominantly adult athletes, it is necessary to validate the method in adolescent athl...

The Androgen Receptor (AR) is a ligand dependent transcription factor that regulates the development and maintenance of the male reproductive system. Previous studies in AIS have demonstrated ligand binding domain mutations resulting in decreased trans-activation activity through reduced N-terminal/C-terminal interaction of the AR, despite unaltered ligand binding ability.We have introduced mutations in the hinge region of the Androgen Receptor (AR) and assessed the effect...

Cushing’s syndrome, which is characterised by excessive circulating glucocorticoid (GC) concentrations, may be due to ACTH-dependent or -independent causes that include anterior pituitary and adrenal cortical tumours, respectively. In the course of our phenotype-driven screens of mouse mutants induced by the chemical mutagen N-ethyl-N-nitrosourea (ENU), we observed a mutant mouse with obesity, hyperglycaemia and low bone mineral density, features that ar...

Purpose: Clinically Non-Functioning Pituitary Neuroendocrine Tumours (NF-PitNETs) present a varying degree of aggressiveness, and reliable prognostic markers are lacking. We aimed to characterize the distribution of E- and N-cadherin in corticotroph, PIT1 and null-cell NF-PitNETs, and link it to the clinical course of the tumours.Methods: We investigated the distribution of E- and N-cadherin by immunohistochemistry in a retrospective cohort of thirty tum...