Endocrine Abstracts

The ghrelin system comprises ghrelin, des-acyl ghrelin and obestatin, besides ghrelin receptor, GH secretagogue receptor type 1a (GHS-R1a), and the enzyme promoting ghrelin acylation, ghrelin-O acyl transferase (GOAT). The ghrelin peptides display different biological actions, including regulation of energy homeostasis and glucose metabolism, as well as survival and proliferative effects in different cell types. Besides the stomach, where they are mostly produced, ghr...

Ghrelin was identified in the stomach as the endogenous ligand of the GH secretagogue receptor type 1a (GHS-R1a). Acylated ghrelin (AG), through interaction with GHS-R1a, exerts many central and peripheral effects, including stimulation of GH secretion and food intake. Unacylated ghrelin (UAG), although unable to bind the GHS-R1a and devoid of endocrine actions is an active peptide, exerting pleiotropic effects through an unknown receptor. UAG has been shown to act as an antag...

Ghrelin was isolated from the stomach and identified as an endogenous ligand of the growth hormone secretagogue receptor type 1a (GHS-R1a). Numerous studies have demonstrated that acylated ghrelin, besides its main endocrine actions such as stimulation of GH secretion and regulation of energy balance, has a wide spectrum of peripheral activities which engage metabolic, endocrine, cardiovascular, bone and immune systems. It is now clear that also unacylated ghrelin, although un...

Growth hormone-releasing hormone (GHRH) is synthesized in hypothalamic neurons and regulates the secretion of growth hormone (GH) from the pituitary gland. GHRH also displays extra-pituitary activities in a variety of cells and organs expressing both GHRH, GHRH receptor (GHRH-R) and its splice variants (SVs). These include, among others, the retina, pancreas, kidney, skeletal muscle and heart. In the heart, we have demonstrated that GHRH(1-44)NH2 exerts survival and antihypert...

Macrophages play essential roles in the immune defence and their hyperactivation has been implicated in epithelial damage in acute respiratory distress syndrome (ARDS), commonly observed in severe COVID-19 patients. In these cells, SARS-CoV-2 spike (S) protein triggers aberrant production of pro-inflammatory cytokines like interleukin-1 beta (IL-1β), interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α), as well as reactive oxygen species (ROS) and matrix meta...

Obesity is characterized by insulin resistance and pancreatic β-cell dysfunction; moreover, secretion of adipokines from adipocytes may affect metabolic functions in several tissues, including pancreatic β-cells. Extracellular vesicles (EVs), released by cells as exosomes or shedding vesicles, play a key role in cell-to-cell communication, modifying the phenotype and function of recipient cells by delivering proteins, RNAs and microRNAs. The crosstalk between adipocy...

Human malignant pleural mesothelioma (MPM) is a rare but aggressive neoplasm, arising from pleural mesothelial cells, generally due to asbestos exposure. Different growth factors are involved in the pathogenesis of MPM and in resistance to therapy; moreover, chemotherapy with cisplatin and antifolates, like pemetrexed (PEM), is the first-line treatment for inoperable MPM. Growth hormone-releasing hormone (GHRH), apart from stimulating GH secretion in the pituitary, exerts many...

White adipose tissue (WAT) stores excess energy as triglycerides, while brown adipose tissue (BAT) dissipates energy through heat, acting as a defense against cold and obesity and as a positive regulator of metabolic functions. The thermogenic function of BAT is mainly regulated by the mitochondrial uncoupling protein 1 (UCP1) in brown adipocytes. Moreover, it has been shown that chronic exposure to glucocorticoids (GC) or synthetic GC receptor (GR) agonists inhibits the activ...

Neurogenesis, a process by which new neurons are generated from precursors, still persists in discrete regions of the adult hippocampus. Impairment in neurogenesis is an important feature in the pathogenesis of neurodegenerative diseases, such asAlzheimer’s disease (AD). The hippocampus is critical for learning and memory and is a main target of AD, which causes massive neuronal death, reduction in neurogenesis and impairment in cognitive functions. Therefore, preventing...

Type II diabetes is a clinical disorder of glucose and fat metabolism, caused by an inability of insulin to promote sufficient glucose uptake into adipose tissue and striated muscle and to prevent glucose output from the liver. Skeletal muscle is an important element for the maintenance of glucose homeostasis because it can increase, after stimulation, glucose uptake from the blood. In previous experiments we found that acylated ghrelin (AG), unacylated ghrelin (UAG), obestati...