Endocrine Abstracts

Food intake is centrally regulated in hypothalamic nuclei. Peripheral hormonal signals activate their corresponding receptors in the arcuate nucleus (arc) and modulate the expression of pro-opiomelanocortin (POMC) and neuropetide Y (NPY)/agouti-related-protein (AgRP). Cleavage products of POMC stimulate melanocortin-4-receptors (MC4R) in the paraventricular nucleus (PVN) to inhibit food intake or stimulate MC3Rs in the arc to activate a feedback loop. Further mor...

Adiposity predisposes to insulin resistance and type II diabetes. Adipose tissue is an active endocrine organ, secreting adipokines with important physiological actions. Adiponectin is a recently discovered adipokine whose levels are, paradoxically, decreased in obesity despite the increase in adipocyte mass. Adiponectin suppresses triglyceride accumulation, increases fatty acid oxidation and activates AMP kinase (AMPK) in skeletal muscle, improving insulin signalling, and it ...

Corticotropin releasing hormone (CRH) and its related peptides, urocortins (UCN), are now emerging as critical regulators of energy balance and homeostasis. These peptides exert their effects through activation of two types of CRH receptors (CRH-R1 and CRH-R2). The role of these peptides as regulators of mammalian thermogenesis and their effects on brown adipose tissue (BAT) have been primarily attributed to modulation of brain centres controlling sympathetic outflow. However,...

Objectives: To study the direct effects of fatty acids (FA) and the involvement of the TLR-4/NFκB pathway with respect to the secretion of adipokines and chemokines from adipocytes.Research design and methods: 3T3-L1 adipocytes were stimulated with increasing doses of FA. The secretion of adiponectin, resistin and MCP-1 was measured by ELISA. NFκB p65 nuclear translocation and TLR-4 expression were investigated by Western blot analysis. NF&#954...

Introduction: In humans, testosterone treatment affects body fat distribution and metabolism. The mechanisms involved in these processes are not yet fully understood. We investigated whether sex hormones modulate the expression and activity of type1 11-β-hydroxy-steroid-dehydrogenase (11β-HSD1). 11β-HSD1 catalyses the conversion of inactive cortisone into active cortisol, a key step for the development of functional adipocytes. Based on previous studies an inhib...

Given the importance of transcriptional regulation in metabolic control, we investigated the role of nuclear receptor co-factors in the liver, a key organ in energy homeostasis. Here we show in mice that the expression of receptor interacting protein 140 (RIP140) in the liver is induced in catabolic states like fasting and cancer cachexia. In contrast, chronic high fat diet feeding reduced RIP140 mRNA levels in the liver. Increased hepatic RIP140 in catabolic conditions was as...

The biguanides metformin and phenformin enhance insulin sensitivity and improve glycaemic control in type 2 diabetes. Metformin is the most prescribed oral agent for type 2 diabetes but phenformin has been withdrawn because of its propensity to cause lactic acidosis. Metformin has a major effect in the liver where it reduces glucose output via AMPK activation. As the adipocyte is now considered to be a critical participant in whole-organism metabolic homeostasis we investigate...

Background: The aim of the present study was to represent our summarized results of plasma endothelin-1 (ET-1) level determined in some endocrine diseases like diabetes, hyper- and hypothyroidism, Cushing’s disease, acromegaly and male hypogonadism in which the existence of endothelial dysfunction and increased cardiovascular risk is proved.Patients and results: In patients with type 2 diabetes (n=34), plasma ET-1 (0.9±0.17 pmol/l) corre...

Nissen’s meta-analysis concluded that the use of Rosiglitazone (RSG) was associated with a significant increase in the risk of myocardial infarction. However, none of the analyzed studies took into account the cardiovascular events as primary outcomes, neither were controlled by cardiovascular risk factors.Objectives: 1. To know if there is an association between RSG myocardial infarction OR and the magnitude of the difference in baseline serum lipi...