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Growth hormone (GH) is secreted by the pituitary gland in a pulsatile manner. It is accepted that this pulsatility is primarily controlled by the hypothalamus, although this secretion can also be modulated by factors from GH-targeted organs, the pituitary and other regions of the central nervous systems, or by factors arriving from peripheral organs. In mammals, hypothalamic control of GH pulsatility is classically regulated by the interplay of two opposing hormones, stimulatory GHRH and inhibitory somatostatin (SS). Recognition of the gastric ghrelin peptide as the natural ligand for GH secretagogue receptor type 1a (GHS-R1a) added a new element to the complex physiological regulation of GH secretion and clarified some of its aspects that were previously not fully understood. In this review, we examine data that suggest that ghrelin may regulate GH secretion, as well as ghrelin's possible use as a therapeutic agent., (Copyright © 2013 S. Karger AG, Basel.)

Introduction: Wernicke's encephalopathy (WE) is an underdiagnosed condition, usually associated with alcoholism, and has a worse prognosis if there is a delay in diagnosis. A series of 8 non-alcoholic patients with WE is presented and an assessment is made on whether a delay in diagnosis leads to a worse prognosis., Patients and Methods: The clinical records of patients admitted to 2 university hospitals between 2004 and 2009 with the diagnosis of WE, excluding those with a history of alcoholism, were retrospectively reviewed., Results: The study included 4 men and 4 women aged 35-82 of whom 7 had a history of gastrointestinal pathology, and persistent vomiting was the precipitating factor in 7. Encephalopathy was the most frequent onset symptom (4). The classical triad was present in seven patients. Thiamine levels were low in 3/6 and normal in 3/6 cases. MRI was abnormal in seven patients, with high signal intensity in the diencephalon and mammillary bodies (7), periaqueductal grey matter (6), cortex (3) and cerebellum (1). Seven improved with thiamine. Sequelae were mild in 6, and severe in 2 after 6-12 months of follow-up. All patients with a diagnostic delay less than 18 days had mild sequelae., Conclusions: Non-alcoholic WE frequently occurs after gastrointestinal disturbances that could result in lower thiamine absorption. Whereas thiamine levels can be normal in many cases, in almost all cases the MRI shows signal alterations in typical locations. A delay in the diagnosis, and therefore, in treatment leads to a worse prognosis., (Copyright © 2010 Sociedad Española de Neurología. Published by Elsevier Espana. All rights reserved.)

GH regulates important physiological processes, including somatic growth and development, and carbohydrate and lipid metabolism. GH deficiency and GH replacement therapy exert opposite effects on body composition and fat accumulation, suggesting that GH may directly regulate adipocyte functions. Multiple studies have shown that in tissues previously deprived of GH, short-term stimulation with GH is able to mimic the actions of insulin, including stimulation of amino-acid and glucose transport, and lipogenesis. However, the antagonistic effects of GH on insulin-mediated metabolic responses are well-documented: GH excess in patients with GH-producing pituitary tumors causes hyperinsulinemia, insulin resistance, and even clinical diabetes mellitus. These apparently contradictory effects may be explained at the molecular level by the complex interplay between GH and insulin signaling. In this review, we examine the consequences of acute and chronic effects of GH on visceral fat and on metabolic responses in adipocytes, and discuss experimental data illustrating the integrated crosstalk between GH and insulin.