Endocrine Abstracts

It has been reported that both normal pituitary and pituitary tumours express PPAR gamma, a nuclear hormone receptor, the expression being much more abundant in pituitary tumours. It has also been suggested that PPAR gamma agonists, such as the thiazolidenediones, could be used as a therapeutic option for pituitary tumours. In order to investigate this further, 'Real time' PCR was used to assess PPAR gamma RNA expression, and Western blotting and immunohistochemistry was used ...

Ghrelin is a brain-gut peptide originally identified in the stomach. It binds to and stimulates the growth hormone secretagogue receptor type 1a (GHS-R). The presence of ghrelin in hypothalamic tissue was studied. It has been previously established that neither the synthetic GHSs, nor the endogenous hormone ghrelin, is specific for GH stimulation: they generally also stimulate the HPA axis as well as prolactin release. Since there is no direct stimulatory effect on ACTH releas...

While primary hyperparathyroidism is most commonly due to a parathyroid adenoma, very occasionally it may be secondary to a parathyroid carcinoma. A substantial minority of parathyroid adenomas are due to mutations or transpositions in genes in involved in the regulation of the cell cycle. In particular, at the cell cycle checkpoint which regulates exit from G1 phase, there is an interaction between the cyclins and cyclin-dependent kinases (CDKs); specifically, cyclin D intera...

BACKGROUND: Ghrelin is a novel 28-amino acid peptide which was isolated from the rat stomach and has now been shown to have a widespread tissue distribution. Ghrelin is the endogenous ligand of the growth hormone secretagogue receptor type 1a (GHS-R1a), and stimulates growth hormone (GH) release via the hypothalamus as well as by a direct action on the pituitary GHS-R1a. Ghrelin and the GHS-R1a also coexist within the pituitary. There are conflicting data regarding the effects...

Aim: Clinical acromegaly is characterized by high GH secretion in the presence of high circulating IGF-I levels. We therefore hypothesized that the physiological IGF-I-GH negative feedback loop may be reset in somatotroph adenomas, and we investigated the role of type 1 IGF receptor (IGF-R) and GH receptor (GHR) by quantifying mRNA expression in somatotroph tumours, and investigated the possible presence of mutations of the GHR gene.Methods: Pituitary t...

The proto-oncogene Gsalpha has been implicated in a significant minority of somatotrophinomas, but the search for candidate oncogenes in the remaining somatotrophinomas, and in the great majority of other types of benign pituitary adenomas, has so far been unsuccessful. Microarray-based comparative genomic hybridisation (microarray-CGH) is a novel DNA microarray technique that has been shown to identify gain or loss at the gene level, and has been proposed as a tool to screen ...

Background: We have recently demonstrated universal and high levels of expression of growth hormone in the human colon, despite the absence of GHRH or its receptor. Although ghrelin, recently shown to be an additional endogenous GH secretagogue, is expressed in the human colon, little is known about its distribution within the colon or function and whether any effects are GH-dependent.Aims: To investigate the mRNA expression of ghrelin and ...

MIF can override the anti-inflammatory actions of glucocorticoids during immune response, and thus is an important pro-inflammatory factor. The presence of MIF in the cytoplasm of adenomatous cells of the anterior pituitary has been described, and high levels of MIF in other rapidly-proliferating tissues have been demonstrated. It is hypothesized that MIF release from these cells is influenced by the hypothalamo-pituitary-adrenal axis, and that ACTH and MIF are released simult...

Background: It is often difficult to define the clinical relevance of a novel gene variant. In silico analyses of variants located close to exon–intron-junctions are utilised to predict the result of these basepair changes. We have previously identified two splice-site variants in AIP and confirmed the predicted changes for c.249G>T, p.G83AfsX15 and c.807C>T. We identified the c.469-2A>G heterozygous variant located at the end of intron-3 in a childhood...

Introduction: The hypothalamic hormone orexin-A (OXA) increases food and water intake, regulates the sleep-wake cycle, muscle tone and energy balance. AMP-activated protein kinase (AMPK) is an important metabolic regulator with direct hypothalamic orexigenic and diverse peripheral effects including fat tissue and muscle.Aims: We aimed to study the influence of OXA on the activity of AMPK in the hypothalamus, subcutaneous and visceral adipose tissues, and...