Endocrine Abstracts

Background: Bone turnover is increased in active acromegaly. Despite normalization of bone turnover after treatment, the risk for vertebral fractures remains increased. Gonadal status, but not bone mineral density (BMD) is correlated to vertebral fracture incidence. Trabecular and cortical bone are differentially affected by GH and IGF-1. The trabecular bone score (TBS) is related to bone microarchitecture and provides further information not captured by BMD measurement.<p...

Objective: Transforming growth factor beta receptor 3 like (TGFBR3L) has been recently described as a pituitary-specific membrane protein detected in a proportion of the gonadotroph cells in non-neoplastic and tumour tissue (1). Furthermore, mouse studies have indicated that TGFBR3L is an inhibin B co-receptor that regulates FSH levels (2). We hypothesized that TGFBR3L expression in gonadotroph non-functioning pituitary neuroendocrine tumours (NF-PitNETs) is related to clinica...

Objective: Pasireotide is a second-generation somatostatin receptor ligands (SRLs) with highest affinity for somatostatin receptor (SST)5, followed by SST2. It is considered, so far, in patients resistant to first-generation SRLs, after surgical failure. Histological characteristics and T2-weighted MRI can predict resistance to first-generation SRLs in patients with somatotroph adenomas. Previous studies primarily assessed efficacy of pasireotide as 2nd or 3rd line medical tre...

Background: Real-time reverse transcription quantitative PCR (RT-qPCR) has become the method of choice for quantification of gene expression changes. Inappropriate data normalization and inconsistent data analyses are some limitations of RT-qPCR. Pituitary adenomas are frequent tumours and the interpretation of increasingly published data within this field is hindered by the lack of a proper selection and validation of stably expressed reference genes.Ai...

Context: Angiopoietin-like protein 4 (Angptl4) is a protein involved in lipolysis, that is regulated by non-esterified free fatty acids (FFA). GH promotes lipolysis and increases circulating FFA. Hypothesis: GH increases circulating Angptl4 levels by modulating its expression and secretion from fat and muscle. Angptl4 might be of metabolic relevance for the insulin resistance associated with GH/IGF1 excess or deficiency.Objective: To evaluate Angptl4 in ...

Context: Adipose tissue distribution is closely related to metabolic disease risk. GH reduces visceral and total body adipose tissue mass, while inducing whole body insulin resistance.Objective: To assess the role of visceral adipose tissue and derived adipokines for the systemic insulin resistance and lipid metabolism, before and after treatment in acromegaly.Patients: Sixty-six adult patients with active acromegaly diagnosed betw...

Objective: Cushing’s disease is caused by hypercortisolism due to adrenocorticotropic hormone (ACTH) hypersecretion from functioning pituitary adenomas (FCA). Endoplasmic reticulum (ER) protein processing is important for hormone production and is upregulated in FCA as shown previously. ER protein processing can be disturbed by ER stress. We hypothesized that ACTH production and secretion can be inhibited by agents that cause ER stress by attenuating ER protein processing...

Background: Functioning (FCA) and silent corticotroph (SCA) pituitary adenomas act differently from a clinical perspective, despite both subtypes showing positive ACTH staining by immunohistochemistry. They are challenging to treat, the former due to functional ACTH production and consequently hypercortisolemia leading to Cushing disease, whereas the latter due to invasive and recurrent behaviour. Moreover, the molecular mechanisms behind their distinct behaviour are not clear...

Background: The exact mechanism behind the hypersecretion of ACTH and lack of negative cortisol feedback on POMC regulation in functional corticotroph adenomas (FCA) is unknown. Silent corticotroph adenomas (SCA) express, but do not secrete functional ACTH and have lower POMC expression. Using RT-qPCR and immunohistochemistry, previous studies have identified some POMC-transcription factors, regulators and processing enzymes to be differentially expressed between FCA and SCA. ...

Background: Long standing growth hormone (GH) excess causes the skeletal clinical signs of acromegaly with typical changes in bone geometry including increased cortical bone thickness (CBT). However, a high prevalence and incidence of vertebral fractures has been reported. The aim of this study was to assess the course of cortical bone dimensions in the hip by comparing patients with acromegaly and clinically non-functioning pituitary adenomas (NFPA) at baseline and one year a...