Endocrine Abstracts

Obestatin is a 23-amino acid amidated peptide that is encoded by the ghrelin gene and was therefore presumed to have regulatory effects on pituitary. However, the limited set of studies performed hitherto suggests that obestatin has no major effect on hormone secretion, in vivo or in vitro, from rodent pituitary, whereas no comparable data is still available on primates. Here, primary pituitary cell cultures from a non-human primate (baboon; Papio anubis) served ...

Circulating levels of prolactin are subject to acute and long-term regulation by many factors including oestrogen and dopamine. We have studied the regulation of prolactin promoter activity in living pituitary cells using transgenic Fischer rats in which reporter gene expression is regulated by the human prolactin gene locus (hPRL-d2EGFP). We have previously identified pulsatile prolactin transcription patterns in living lactotroph cells in fetal tissue, that became stabilised...

MicroRNAs (miRNAs) have several physiological functions, but have been also implicated in human neoplastic initiation and progression. We previously demonstrated that 30 miRNAs are differentially expressed in normal human pituitary as compared to pituitary adenomas. However, the most of miRNAs target genes remain unknown, hindering the understanding of the miRNAs contribute to pituitary tumorigenesis.The aims of this study were to: (i) validate a murine ...

In this study we employed a novel bioluminescence resonance energy transfer (BRET) biosensor to study the coupling specificity of somatostatin receptor 5 (SST5) and its naturally occurring mutant R240W in living cells. Our previous data demonstrated that SST5 carrying the R240W mutation as well as other mutations in the third intracellular loop maintained the ability to inhibit intracellular cAMP levels similarly to the wild-type but failed to mediate the inhibition of intrace...

IGF-I receptors (IGF-IR) and their aberrant signaling cascade contribute to the pathogenesis of several solid cancers. Pituitary adenomas express IGF-IR and present with overactivation of the IGF-IR pathway. The aim of the study was to identify the potential antiproliferative action of the small molecule IGF-IR inhibitor NVP-TAE226 on acromegalic (n=11) and nonfunctioning pituitary adenomas (NFPA; n=15) in primary cell culture. Changes in cell viability were dete...

Background: Although pituitary adenomas are common endocrine neoplasms, the background of their pathogenesis has not clearly revealed. G1/S checkpoint alterations of the cell cycle have already been described in these tumours. MicroRNAs (miRs) which are small, non-coding RNA molecules, and posttranscriptionally regulate protein expression have also identified as potential pathogenic factors in certain cases. Our aim was to determine miR expression profile in pituitary adenomas...