Endocrine Abstracts

Heterotrimeric G-proteins are important molecular switches that transduce extracellular ligand-binding at G-protein-coupled receptors (GPCRs) to intracellular signals. G-protein alpha-subunits (Gα) have two domains, a helical and GTPase domain, which provide structural stability and mediate GTPase activity, respectively. Gain-of-function Gα mutations cause endocrine conditions including McCune-Albright Syndrome, due to Gαs mutations, and a...

Introduction: Human leukocyte antigen-G (HLA-G) is a non-classical HLA-class Ib molecule with multiple immunoregulatory properties. Its main role is the maintenance of tolerance between maternal immune system and semiallogenic fetus. The expression of HLA-G antigen has been reported in several cancers and seems to play an important role in the escape of tumour cells from immune surveillance. A 14 bp insertion/deletion polymorphism in exon 8 of the 3′ untranslated region ...

Mutations of the calcium-sensing receptor (CaSR), G-protein alpha-11 subunit (Gα11), and adaptor protein-2 sigma subunit (AP2σ) resulting in a loss-of-function, cause familial hypocalciuric hypercalcemia types 1-3 (FHH1-3), respectively. We investigated a family with FHH (four affected and two unaffected members) for CaSR, Gα11 and AP2σ mutations, and identified a heterozygous Gα11 missense mutation, Phe220Ser, which is predicted to disrupt a cluster o...

IntroductionThe Sodium Iodide Symporter (NIS) is responsible for the active transport of iodide into thyroid cells. Most of differentiated thyroid carcinomas (TC) retain the functional expression of NIS, which allows the use of radioiodide (RAI) as the systemic treatment of choice for metastatic disease. Still, a significant proportion of patients with advanced thyroid cancer fail to respond to RAI therapy (refractory-TC), which makes their management ve...

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 ...

Many studies have shown insulin resistance (IR) in majority of patients with adrenal incidentaloma. The euglycaemic hyperinsulinaemic glucose clamp technique is still considered as ‘golden standard’ for evaluation of insuline sensitivity. These methods are also complicated, labor-intensive procedure better for small research studies. Today, several surrogate indexes for insulin sensitivity were introduced such as: HOMA, QUIQI or G/IR. Some studies showed that QUIQI h...

Introduction: Assessment of adrenal insufficiency (AI) is done routinely through Synacthen test. However, the conventional high dose (250 μg) stimulation is supra-physiological, therefore 1 μg low dose test was developed.Aim: to investigate the utility of the Low-dose test vs the High-dose test, in patients with suspected central AI, in a tertiary centre of endocrinology, in the National Institute of Endocrinology, Bucharest, Romania.<p cla...

Type 1 diabetes (T1D) is a complex autoimmune disease. Several genetic loci have been implicated in the susceptibility to this illness. Evaluated was the role of the CTLA4 exon 1 A49G polymorphism and its role as a risk factor for T1D in our population. DNA from 120 patients with T1D and 96 control individuals were genotyped for CTLA4 exon 1 polymorphism by polymerase chain reaction (PCR) amplification-restriction enzyme analysis and PCR amplification that used sequence-specif...

Together with Profs Lefkowitz and Kobilka, G-protein-coupled receptors (GPCRs) have taken the stage in the 2012 Nobel award for Chemistry. The Royal Swedish Academy of Sciences states that ‘About half of all medications achieve their effect through G-protein-coupled receptors’. As shown in previous talks in this session, GPCRs are not acting individually; often they form homodimers and, more interestingly, they may occur as heterodimers. Heteromers open a completely ...

Background: Diabetic retinopathy (DR) is a chronic diabetic complication occurring in most diabetic patients after 20 years of disease. Progression of DR to its sight threatening stages is usually associated with worsening of underlying retinal vascular dysfunction and disease. The plasma kallikrein kinin system is activated during vascular injury, mediating important functions in inflammation, blood flow, and coagulation. Bradykinin B1 receptor (B1R) is expressed in human ret...