Endocrine Abstracts

Dopamine agonists (DA) inhibit prolactin (PRL) secretion and expression on the pituitary lactotrophs by binding dopamine D2 receptor. Prolactinomas are the most common secreting pituitary adenomas, and DA are the first choice for their treatment because they reduce PRL levels and tumor size. However, a subset of patients is resistant to DA. The mechanisms involved in DA resistance are not fully understood, although decreased expression of D2 receptor or altered signal transduc...

The connective tissue components, collagen types I, III and IV, which surround the ovarian follicles, undergo drastic changes during ovulation. Abnormal collagen synthesis and increased volume and density of ovarian stroma characterise the polycystic ovary syndrome (PCOS). Physiologically, collagen synthesis in ovarian follicles is partly regulated by lysyl oxidase (LOX), which catalyzes the collagen and elastin cross-linking and plays indispensable role in the organization of...

Besides their well-known anti-diabetic effects, the peroxisome proliferator-activated receptor γ (PPARγ) thiazolidinedione ligands (TZD) have been suggested to also display anti-inflammatory properties. The receptor role in mediating such effects is far from being elucidated. Here, we demonstrate that PPARγ is necessary for TZD to interfere with TNFα and IFNγ inflammatory activity in human endothelial cells. Different PPARγ ligands similarly inhib...

TSH regulates thyroid function trough the receptor coupled to heterotrimeric G-protein composed of α, β and gamma subunits. The activation of α s /adenylyl cyclase mediated pathway accounts for most of TSH biological effects. TSH can also induce the other G-α protein mediated activities. Five different isoforms of β subunit have been described and it can be assumed that specific α-β combination are essential for functional differentiation of ...

Somatotroph adenomas are characterized by growth hormone hypersecretion and cell proliferation. We have previously identified crosstalk between the cAMP pathway and the MAPKinases ERK1/2 cascade and shown the central place of the MAPKinases in the control of the pituitary function in GH4C1 somatolactotroph cell line.The spatio-temporal organization of the signalling partners governs signalling fidelity and encodes the specificity of biological responses....

ICH is a heterogeneous disease mainly due to functional defects of GnRH neurons. Recent studies have described the importance of prokineticin pathway in the pathogenesis of these defects. In a series of 166 ICH patients we found germline mutations affecting this pathway in about 10% of the cases. PROKR2 gene analysis revealed 3 novel (V158I, T260M, V334M) and 4 already known (L173R, R268C, V274D, V331M) mutations affecting different transmembrane and intracellular regions of t...