Endocrine Abstracts

One of the hallmarks of parturition in most mammals is a dramatic drop in plasma levels of progesterone (P4), which promotes myometrial relaxation, prior to labor. In humans and some other primates however, the opposite occurs and placental P4 production increases with advancing pregnancy. The expression of nuclear progesterone receptor (PR)-responsive genes is decreased in the primate uterus at term, which suggests ‘functional’ progestin withdrawal involves repressi...

The physiological effects of the pituitary hormone, adrenocorticotropic hormone (ACTH) on the adrenal are mediated by the melanocortin 2 receptor (MC2R), a G protein coupled receptor (GPCR) that signals via adenylate cyclase to elevate intracellular cyclic AMP (cAMP) levels. Therefore the expression and function of the receptor are likely to be the major determinants of the response to ACTH. Following repeated stimulation, the cAMP signal is diminished or desensitised. Desensi...

A variety of rapid responses to steroid hormones have been identified during the last decade. In contrast to classical actions mediated via nuclear receptors with a time lag of hours, rapid actions occur within seconds or minutes via second messenger signalling cascades. Classical genomic actions are well-defined and sensitive to transcription and protein synthesis inhibitors. Steroid hormones enter the cell by diffusion or via transport proteins and bind to cognate receptors ...

Mechanisms regulating the selection of antral ovarian follicles are poorly understood and supposed to rely on low estrogen levels, decline of follicle-stimulating hormone (FSH) levels and receptor (FSHR) expression on the surface of granulosa cells. These concepts are challenged in-vitro, where apoptosis of human granulosa cells (hGLC) and transfected cell lines is induced by high doses of FSH or FSHR overexpression, while estrogens induce anti-apoptotic signals via n...

Somatostatin and dopamine receptors are the major Gi-coupled receptors in somatotrope cells that inhibit hormone secretion from the anterior pituitary. Here, we adapted a novel fluorescence-based screening assay to characterize somatostatin and dopamine receptor signaling in a time-resolved manner. This minimal-invasive technique provides a robust and reliable read out for ligand-induced receptor activation in permanent cell lines and primary pituitary culture. The ...

G protein-coupled receptors (GPCRs) are critical for signal transduction within neuroendocrine signalling pathways, and genetic mutations in G protein-coupled GPCRs underlie numerous diseases. Inactivating GPCR mutations can impede ligand interactions or signal transduction, or can result in misfolding of nascent receptor proteins and subsequent retention in the endoplasmic reticulum (ER) and thus failure to traffic to the cell surface. Examination of the functionality and cel...

Excessive expression of CyD1 in CCND1 gene increase G1-S phase transition and cellular proliferation. In various tumor types and of the few studies of pituitary adenomas, over expression of CyD1 or amplification in the locus of CCND1 gene, have been demonstrated. In this study, we aimed to investigate the effect of cyclin D1 gene polymorphism on tumor formation in prolactinoma patients.A hundred and thirteen patients and 108 age and gender matched contro...

Background: One of the basic genetic factors that impact on development of diabetic nephropathy is enhanced expression of vascular endothelial growth factor (VEGF).Objective: To study association between VEGF polymorphism +405 G/C and early stage of chronic kidney disease (CKD) in patients with impaired glycemic states.Materials and methods: 73 included patients were divided into three groups: group 1–26 patients with prediabe...

Oestrogenic effects on colorectal cancer (CRC) incidence, proliferation, and patient survival remains controversial. We have previously shown enzymic pathways favouring oestradiol (E2) synthesis are upregulated in CRC, and stimulation of the G-protein coupled oestrogen receptor (GPER) by E2 increases CRC proliferation. Here we interrogated The Cancer Genome Atlas (TCGA) Colon Adenocarcinoma (COAD) database to determine all oestrogen metabolism enzymes and...

Oestrogenic effects on colorectal cancer (CRC) incidence, proliferation, and patient survival remains controversial. We have previously shown enzymic pathways favouring oestradiol (E2) synthesis are upregulated in CRC, and stimulation of the G-protein coupled oestrogen receptor (GPER) by E2 increases CRC proliferation. Here we interrogated The Cancer Genome Atlas (TCGA) Colon Adenocarcinoma (COAD) database to determine all oestrogen metabolism enzymes and...