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Pituitary adenomas are uncommon, difficult to diagnose tumors whose heterogeneity and low incidence complicate large-scale studies. The Molecular Registry of Pituitary Adenomas (REMAH) was promoted by the Andalusian Society of Endocrinology and Nutrition (SAEN) in 2008 as a cooperative clinical-basic multicenter strategy aimed at improving diagnosis and treatment of pituitary adenomas by combining clinical, pathological, and molecular information. In 2010, the Spanish Society of Endocrinology and Nutrition (SEEN) extended this project to national level and established 6 nodes with common protocols and methods for sample and clinical data collection, molecular analysis, and data recording in a common registry (www.remahnacional.com). The registry combines clinical data with molecular phenotyping of the resected pituitary adenoma using quantitative real-time PCR of expression of 26 genes: Pituitary hormones (GH-PRL-LH-FSH-PRL-ACTH-CGA), receptors (somatostatin, dopamine, GHRH, GnRH, CRH, arginine-vasopressin, ghrelin), other markers (Ki67, PTTG1), and control genes. Until 2015, molecular information has been collected from 704 adenomas, out of 1179 patients registered. This strategy allows for comparative and relational analysis between the molecular profile of the different types of adenoma and the clinical phenotype of patients, which may provide a better understanding of the condition and potentially help in treatment selection. The REMAH is therefore a unique multicenter, interdisciplinary network founded on a shared database that provides a far-reaching translational approach for management of pituitary adenomas, and paves the way for the conduct of combined clinical-basic innovative studies on large patient samples.

Pituitary adenomas are uncommon, difficult to diagnose tumors whose heterogeneity and low incidence complicate large-scale studies. The Molecular Registry of Pituitary Adenomas (REMAH) was promoted by the Andalusian Society of Endocrinology and Nutrition (SAEN) in 2008 as a cooperative clinical-basic multicenter strategy aimed at improving diagnosis and treatment of pituitary adenomas by combining clinical, pathological, and molecular information. In 2010, the Spanish Society of Endocrinology and Nutrition (SEEN) extended this project to national level and established 6 nodes with common protocols and methods for sample and clinical data collection, molecular analysis, and data recording in a common registry (www.remahnacional.com). The registry combines clinical data with molecular phenotyping of the resected pituitary adenoma using quantitative real-time PCR of expression of 26 genes: Pituitary hormones (GH-PRL-LH-FSH-PRL-ACTH-CGA), receptors (somatostatin, dopamine, GHRH, GnRH, CRH, arginine-vasopressin, ghrelin), other markers (Ki67, PTTG1), and control genes. Until 2015, molecular information has been collected from 704 adenomas, out of 1179 patients registered. This strategy allows for comparative and relational analysis between the molecular profile of the different types of adenoma and the clinical phenotype of patients, which may provide a better understanding of the condition and potentially help in treatment selection. The REMAH is therefore a unique multicenter, interdisciplinary network founded on a shared database that provides a far-reaching translational approach for management of pituitary adenomas, and paves the way for the conduct of combined clinical-basic innovative studies on large patient samples.

Adipose tissue (AT) dysfunction in obesity is commonly linked to insulin resistance and promotes the development of metabolic disease. Bariatric surgery (BS) represents an effective strategy to reduce weight and to improve metabolic health in morbidly obese subjects. However, the mechanisms and pathways that are modified in AT in response to BS are not fully understood, and few information is still available as to whether these may vary depending on the metabolic status of obese subjects. Abdominal subcutaneous adipose tissue (SAT) samples were obtained from morbidly obese women (n = 18) before and 13.3 ± 0.37 months after BS. Obese women were stratified into two groups: normoglycemic (NG; Glu

Objective To assess the utility of the desmopressin (DDAVP) test in the diagnosis and follow-up of a cyclical Cushing's disease (CCS) case. Material and methods Laboratory tests included morning and midnight serum cortisol levels, 24 h urine free cortisol excretion, midnight salivary cortisol levels, serum cortisol levels after low (1 mg) and high (8 mg) dexamethasone, plasma ACTH and serum cortisol levels after DDAVP. Magnetic resonance imaging (MRI) was used to assess the presence of a pituitary adenoma. The resected tumor specimen was studied by histological, immunohistochemical and cell biology techniques. Results A patient was referred to our unit with a diagnosis of Cushing's syndrome (CS) for further evaluation and treatment. However, no biochemical evidence of hypercortisolism was observed in the follow-up evaluations. Furthermore, the typical features of CS fluctuated throughout this period. A consistent positive response to the DDAVP stimulation test was observed during the diagnostic work-up, even when overt clinical features of CS were not apparent, raising suspicion for CCS. After two years of follow-up a definitive diagnosis of hypercortisolism was established. An MRI scan revealed a pituitary adenoma, as the source of ACTH production. After transphenoidal surgery, clinical signs of CS resolved and the response to DDAVP became negative. DDAVP induced a significant increase in ACTH levels in cultured pituitary adenoma cells, consistent with the in vivo DDAVP test results. Conclusions Our case illustrates the utility of the DDAVP test in the evaluation of patients with suspected CCS. The DDAVP test could facilitate the management of CCS by shortening the time of diagnosis.

Luque, Raúl M. et al., [Context] Desmopressin is a synthetic agonist of vasopressin receptors (AVPRs). The desmopressin stimulation test is used in the diagnosis and postsurgery prognosis of Cushing disease (CD). However, the cellular and molecular mechanisms underlying the desmopressin-induced ACTH increase in patients with CD are poorly understood. [Objective] The objectives of this study were to determine, for the first time, whether desmopressin acts directly and exclusively on pituitary corticotropinoma cells to stimulate ACTH expression/release and to elucidate the cellular and molecular mechanisms involved in desmopressin-induced ACTH increase in CD., [Design] A total of 8 normal pituitaries (NPs), 23 corticotropinomas, 14 nonfunctioning pituitary adenomas, 17 somatotropinomas, and 3 prolactinomas were analyzed for AVPR expression by quantitative real-time RT-PCR. Primary cultures derived from corticotropinomas, nonfunctioning pituitary adenomas, somatotropinomas, prolactinomas, and NPs were treated with desmopressin, and ACTH secretion/expression, [Ca2+]i kinetics, and AVPR expression and/or proliferative response were evaluated. The relationship between AVPR expression and plasma adrenocorticotropin/cor-tisol levels obtained from desmopressin tests was assessed., [Results] Desmopressin affects all functional parameters evaluated in corticotropinoma cells but not in NPs or other pituitary adenomas cells. These effects might be due to the dramatic elevation of AVPR1b expression levels found in corticotropinomas. In line with this notion, the use of an AVPR1b antagonist completely blocked desmopressin stimulatory effects. Remarkably, only AVPR1b expression was positively correlated with elevated plasma adrenocorticotropin levels in corticotropinomas., [Conclusions] The present results provide a cellular and molecular basis to support the desmopressin stimulation test as a reliable, specific test for the diagnosis and postsurgery prognosis of CD. Furthermore, our data indicate that AVPR1b is responsible for the direct/exclusive desmopressin stimulatory pituitary effects observed in CD, thus opening the possibility of exploring AVPR1b antagonists as potential therapeutic tools for CD treatment. Copyright © 2013 by The Endocrine Society., Funding organizations are Junta de Andalucia, Ministerios de Economía y Competitividad y Sanidad, Servicios Sociales e Igualdad, Ciber, Merck Serono, ISCIII (Spain).

Patients with adult GH deficiency (AGHD) have a high cardiovascular risk and probably an alteration of the oxidative balance, although evidence is lacking. To evaluate the presence of endothelial dysfunction and oxidative stress in patients with AGHD. Biochemical parameters of oxidative stress and endothelial dysfunction were compared in 25 patients with previously untreated AGHD and 25 healthy controls matched by age and sex. Multivariate analysis was performed to identify independent predictors of oxidative stress. Vascular function of subcutaneous resistance arteries was also analyzed by means of wire myography in 7 patients with untreated AGHD and in 7 healthy controls with similar characteristics. The values of C-reactive protein, interleukin-6 (IL-6) and tumour necrosis factor alpha (TNF-α), were higher in the AGHD group (4.6 vs. 0.2 μg/L, P = 0.02; 5.6 vs. 1.2 pg/mL, P = 0.001; 6.7 vs. 2.1 pg/mL, P = 0.04; respectively). The levels of type-1 vascular cell adhesion molecule, total anti-oxidant state, oxidized LDL (LDL-ox) were also greater in AGHD patients (678 vs. 423 ng/mL, P = 0.004; 1235.6 vs. 1002.3 μmol/L, P = 0.01; 172.2.5 vs. 42.3 ng/mL, P = 0.02; respectively). Nitric oxide (NO), reduced glutathione (GSH) and reduced/oxidized glutathione ratio (GSH/GSSG) values were lower than controls (18.7 vs. 31.6 mmol/mg protein, P = 0.01; 372.2 vs. 756.2 μmol/L, P = 0.03; 17.2 vs. 38.4, P = 0.04; respectively). Multiple regression analysis showed that AGHD was an independent predictor of increased LDL-ox (P = 0.002) and decreased GSH (P = 0.000). Furthermore, the degree of vascular relaxation to repeated exposure of acetylcholine was lower in AGHD (P = 0.025). Patients with AGHD have an increased degree of oxidative stress and endothelial dysfunction that could already be present in early stages of the disease. Studies with a greater number of patients are needed in order to confirm our findings.

ContextKISS1 was originally identified as a metastasis-suppressor gene able to inhibit tumor progression. KISS1 gene products, the kisspeptins, bind to a G-protein-coupled receptor (KISS1R, formerly GPR54), which is highly expressed in placenta, pituitary, and pancreas, whereas KISS1 mRNA is mainly expressed in placenta, hypothalamus, striatum, and pituitary.Objective and designKISS1/KISS1R pituitary expression profile, coupled to their anti-tumoral capacities, led us to hypothesize that this system may be involved in the biology of pituitary tumors. To explore this notion, expression levels of KISS1R and KISS1 were evaluated in normal and adenomatous pituitaries. Additionally, functionality of this system was assessed by treating dispersed pituitary adenoma cells in primary culture with kisspeptin-10 and evaluating intracellular calcium kinetics and apoptotic rate.ResultsBoth KISS1 and KISS1R were expressed in normal pituitary, whereas this simultaneous expression was frequently lost in pituitary tumors, where diverse patterns of KISS1/KISS1R expression were observed that differed among distinct types of pituitary adenomas. Measurement of calcium kinetics revealed that kisspeptin-10 elicits a remarkable increase in [Ca2+]i in individual cells from four out of the five GH-producing adenomas studied, whereas cells derived from non-functioning pituitary adenomas (NFPA, n=45) did not respond. In contrast, kisspeptin-10 treatment increased the apoptotic rate in cells derived from both GH-producing and NFPA.ConclusionsThese results provide primary evidence that KISS1 and KISS1R expression can be differentially lost in pituitary tumor subtypes, where this system can exert functional, proapoptotic actions, and thereby offer novel insights to investigate the biology and therapeutic options to treat these tumors.

La aplicacion de nuevas tecnicas y metodologias moleculares y celulares esta permitiendo alcanzar avances signifi cativos en el conocimiento de los mecanismos que subyacen a la aparicion y la persistencia de las diversas enfermedades que afectan a la glandula hipofi saria. Estudios multidisciplinarios, llevados a cabo tanto en modelos animales como en lineas celulares o muestras tumorales humanas, permiten descubrir nuevas moleculas y potenciales dianas terapeuticas. En los Congresos de la Endocrine Society y de la Pituitary Society celebrados en junio de 2009 en Washington, Estados Unidos, se presentaron numerosos ejemplos de como estas nuevas aproximaciones estan ayudando a mostrar el camino de las futuras investigaciones clinicas dirigidas a la busqueda de nuevas terapias, mas efectivas. En efecto, en ambos congresos se han dado a conocer nuevas herramientas moleculares que podrian llegar a facilitar el diagnostico, aportar informacion sobre el pronostico y orientar al clinico hacia el tratamiento mas efectivo. Actualmente, el desarrollo de nuevas tecnologias como el analisis de curvas de fusion de alta resolucion (high resolution melting), el analisis de expresion de micro-ARN (miRNAs) y la pirosecuenciacion abren un nuevo panorama de estudio que puede aportar informacion defi nitiva sobre la oncogenesis de los tumores hipofi sarios y ayudar a predecir su comportamiento y su sensibilidad a farmacos en funcion de su genotipo y su fenotipo molecular. En defi nitiva, el conocimiento de la biologia molecular de las neoplasias hipofi sarias ha experimentado en los ultimos anos avances considerables que permiten conocer muchas de las alteraciones geneticas que contribuyen al desarrollo de estos tumores; sin embargo, aun es necesario continuar esclareciendo las relaciones entre estas alteraciones geneticas y el comportamiento clinicopatologico del tumor. A continuacion se presentan de forma resumida las comunicaciones cientifi cas que consideramos mas destacadas en este campo, tanto en formato oral como poster, de las que se presentaron en esta reunion.

Cushing's syndrome results from prolonged exposure to excessive circulating glucocorticosteroids and is associated with significant morbidity and mortality. While the treatment of choice in most patients is surgical, the metabolic consequences of this syndrome, including hypertension and diabetes mellitus, increase the risks of such surgery. Hypercortisolemia and its sequelae can be efficiently reversed or controlled using medical therapy, either as a temporary measure prior to definitive treatment or as a longer-term treatment in some particularly difficult cases. Drug treatment has been targeted at the hypothalamic/pituitary level, the adrenal glands and at glucocorticoid receptors. The present review discusses the pharmacotherapeutic agents that have been used in Cushing's syndrome and the criteria for their use, as well as recent drugs that may improve the medical treatment of this complex endocrinological disorder in the future. Finally, the short-and long-term follow-up of patients with Cushing's syndrome after surgery is also discussed.

Summary Objective Glucocorticoid excess is commonly related to neuropsychiatric and neurological disorders, with memory impairment typically found among these disorders. The objective of this study is to offer a clinical profile of memory deficits resulting from exposure to chronic stress-level elevations of endogenous glucocorticoids in patients with Cushing's Syndrome (CS). Study subjects Thirty female participants of matching age and education level were studied: 15 had untreated CS (mean age 38 ± 14) and 15 were healthy. In all patients, CS was confirmed by histology of the lesion after surgery. Design Different learning and memory processes were assessed using an adapted version of Luria's Memory Words-Revised task (LMW-R). Participants’ performances were measured in an immediate condition and, 30 min later, in a delayed condition. Attentional and executive functions were also evaluated. Results Our data show that chronic exposure to elevated levels of cortisol is clinically associated with significant working memory deficits, which included less shot-term memory volume, slow learning rate, memory contamination and no accurate perception of own performance. Patients also show impairment in the delayed recall task. No relation was detected between learning and delayed conditions. CS group did not differ significantly from control group in basic attentional and executive functioning. Conclusions Our clinical profile of memory deficits related to CS relates chronic exposure to hypercortisolemia to impaired attentional-dependent working memory and delayed recall process, suggesting that cortisol levels play a critical role in the modulation of learning and memory. Possible damage to hippocampus and extrahippocampal areas is discussed.

Objetivo Analizar las caracteristicas de la function hipofisaria en la fase inicial de pacientes criticos con traumatismo craneoencefalico grave (TCEG). Diseno Estudio observacional, prospectivo. La funcion hipofisaria se evaluo siempre el tercer dia tras el TCEG. Ambito Unidad de cuidados intensivos (UCI) neurotraumatologica de un hospital universitario. Pacientes Se incluyo a 136 pacientes con TCEG (intervalo, 16-65 anos), durante un periodo de 2 anos y 9 meses y estancia en UCI mayor de 48 h. Intervencion Ninguna. Medidas y datos recopilados Se recogieron durante las primeras 72 h tras el traumatismo: variables demograficas, severidad de la lesion, parametros de neuromonitorizacion, lesiones cerebrales secundarias, uso de farmacos vasoactivos y el tipo de traumatismo craneoencefalico (TCE) acorde a los hallazgos encontrados en la tomografia computarizada (TC). La evaluacion de la function hipofisaria se determino por medicion de hormonas hipofisarias y las de los organos diana, con la excepcion de la funcion somatotropa, que se evaluo midiendo las concentraciones sericas basales de insulin-like growth factor-1 (IGF-1). Resultados Se observo disfuncion hipofisaria en 101 (74,2%) pacientes; 79 (58%) pacientes tenian afectado solamente un eje hipofisario, la afectacion de ejes es la siguiente: gonadotropo, el 63,7% (87 pacientes); tirotropo, el 8,8% (12 pacientes), y corticotropo, el 0,7% (1 paciente). Se observaron concentraciones plasmaticas bajas de IGF-1 acorde a la edad en 90 (66,7%) pacientes, aunque solo 26 de ellos mostraron un valor menor de 90 ng/ml. Conclusiones Nuestros datos muestran que la disfuncion hipofisaria ocurre precozmente y con gran frecuencia tras un TCEG, aunque el significado real de estos hallazgos estan aun por determinar.

Context: Rab proteins regulate the sequential steps of intracellular membrane transport. Alterations of these GTPases and their associated proteins are emerging as the underlying cause for several human diseases involving dysregulated secretory activities. Objective: Herein we investigated the role of Rab18, which negatively regulates hormone secretion by interacting with secretory granules, in relation to the altered functioning of tumoral pituitary somatotropes causing acromegaly. Patients: A total of 18 patients diagnosed with pituitary tumors causing acromegaly (nine patients) or nonfunctioning adenomas (nine patients) underwent endoscopic transsphenoidal surgery. Adenomas were subsequently processed to evaluate Rab18 production in relation to GH secretion. Results: We found that somatotropinoma cells are characterized by a high secretory activity concomitantly with a remarkably reduced Rab18 expression (15%) and protein content levels (30%), as compared with cells from nonfunctioning pituitary adenomas derived from patients with normal or reduced GH plasma levels (100%). Furthermore, immunoelectron microscopy revealed that Rab18 association with the surface of GH-containing secretory granules was significantly lower in somatotropes from acromegalies than nonfunctioning pituitary adenomas. Finally, we provide evidence that modulation of Rab18 gene expression can revert substantially the hypersecretory activity of cells because Rab18 overexpression reduced by 40% the capacity of cells from acromegalies to respond to GHRH stimulation. Conclusion: These results suggest that molecular alterations affecting individual components of the secretory granule traffic machinery can contribute to maintain a high level of GH in plasma. Accordingly, Rab18 constitutes a valuable target as a diagnostic, prognostic, and/or therapeutic tool for human acromegaly.

Pituitary adenomas are uncommon, difficult to diagnose tumors whose heterogeneity and low incidence complicate large-scale studies. The Molecular Registry of Pituitary Adenomas (REMAH) was promoted by the Andalusian Society of Endocrinology and Nutrition (SAEN) in 2008 as a cooperative clinical-basic multicenter strategy aimed at improving diagnosis and treatment of pituitary adenomas by combining clinical, pathological, and molecular information. In 2010, the Spanish Society of Endocrinology and Nutrition (SEEN) extended this project to national level and established 6 nodes with common protocols and methods for sample and clinical data collection, molecular analysis, and data recording in a common registry (www.remahnacional.com). The registry combines clinical data with molecular phenotyping of the resected pituitary adenoma using quantitative real-time PCR of expression of 26 genes: Pituitary hormones (GH-PRL-LH-FSH-PRL-ACTH-CGA), receptors (somatostatin, dopamine, GHRH, GnRH, CRH, arginine-vasopressin, ghrelin), other markers (Ki67, PTTG1), and control genes. Until 2015, molecular information has been collected from 704 adenomas, out of 1179 patients registered. This strategy allows for comparative and relational analysis between the molecular profile of the different types of adenoma and the clinical phenotype of patients, which may provide a better understanding of the condition and potentially help in treatment selection. The REMAH is therefore a unique multicenter, interdisciplinary network founded on a shared database that provides a far-reaching translational approach for management of pituitary adenomas, and paves the way for the conduct of combined clinical-basic innovative studies on large patient samples. (C) 2016 SEEN. Published by Elsevier Espana, S.L.U. All rights reserved.

Objective Traumatic brain injury (TBI) has been associated with hypopituitarism and GH deficiency. However, TBI-mediated hypopituitarism may be more frequent than previously thought. The present work, performed in patients with severe TBI at least 1 year before, had three aims: (i) to evaluate the prevalence of hypopituitarism, (ii) in particular to evaluate the prevalence of GH deficiency, and (iii) to compare three different tests of GH reserve in this cohort. Design and patients From a nonselected group of 249 patients admitted to our Clinical Centre for severe TBI over the last 5 years, 200 of them answered a custom made questionnaire of symptoms of hypopituitarism enclosed in the invitation letter to participate in the study. A total of 170 (99 men and 14 women), accepted to participate in the study (study cohort); 57 had normal questionnaires and were not further studied, 14 discontinued the study, and 99 attended the hospital for dynamic tests of pituitary hormone deficiencies. From these, 44 subjects with IGF-I in the lower range were tested with GHRH+GHRP-6; ITT; and glucagon tests of GH reserve, on three different occasions. Measurements Pituitary hormones plus IGF-I and target gland hormones were analysed. Results With regard to the initial cohort of 170 subjects (100%), three (1.7%) showed diabetes insipidus; 10 (5.8%) TSH deficiency, 11 (6.4%) ACTH deficiency and 29 (17%) gonadotrophin deficiency. In 10 subjects (5.8%), GH deficiency was diagnosed by strict criteria. Finally, 15 (8.8%) showed combined deficit of several hormones. Conclusion After severe head trauma, gonadotrophin deficiency was the most common pituitary deficit. GH deficiency showed a prevalence similar to ACTH and TSH deficits, i.e. near 6% of the cohort. Taken together, 24.7% of the subjects studied showed any type of pituitary hormone deficiency.

BACKGROUND: In type 1 diabetes mellitus (DM1), high GH basal levels and exaggerated responses to several stimuli have been described. Acipimox is an antilipolytic drug that produces an acute reduction of free fatty acids (FFA). The aim of this study was to evaluate the effect of the reduction of plasma FFA with acipimox, alone or in combination with GHRH, on GH secretion in DM1. METHODS: Six type 1 diabetic patients were studied (three women, three men), mean age of 30±2.1 years, body mass index (BMI) 23.1± 1.5 kg/m2. As a control group, six normal healthy subjects of similar age, sex and weight were studied. Each patient and control received GHRH [1 μg/kg intravenously (i.v.) at min 180], acipimox (250 mg orally at min 0 and 120) and GHRH plus acipimox on three separated days. Subjects served as their own control. Blood samples were taken at appropriate intervals for determination of GH, FFA and glucose. RESULT: In control subjects, the GH area under the curve (AUC; μg/l x 120 min) was for acipimox-treated 1339 ± 292 and 1528 ± 330 for GHRH-induced secretion. The GH AUC after the administration of GHRH plus acipimox was 3031 ± 669, significantly greater than the response after acipimox alone (P < 0-05) or GHRH alone (P < 0.05). In diabetic patients, the GH AUC was for acipimox-treated 2516 ± 606 and 1821 ± 311 for GHRH-induced secretion. The GH AUC after the administration of GHRH plus acipimox was 7311 ± 1154, significantly greater than the response after acipimox alone (P < 0.05) or GHRH alone (P < 0.05). The GH response after acipimox was increased in diabetic when compared with normal (P < 0.05), with a GH AUC of 1339 ± 292 and 2515 ± 606 for normal subjects and diabetic patients, respectively. The GH response after acipimox plus GHRH was increased in diabetic when compared with normal (P < 0.05), with a GH AUC of 3031 ± 669 and 7311 ± 1154 for normal subjects and diabetic patients, respectively. The administration of acipimox induced a FFA reduction during the entire test. CONCLUSIONS: Reduction of free fatty acids with acipimox is a stimulus for GH secretion in DM1. The combined administration of GHRH plus acipimox induces a markedly increased GH secretion in type 1 diabetic patients when compared with normal subjects. These data suggest that patients with DM1 exhibit a greater GH secretory capacity than control subjects, despite the fact that endogenous FFA levels seems to exert a greater inhibitory effect on GH secretion in these patients.

et al., Acromegaly is a disorder resulting from excessive production of growth hormone (GH) and consequent increase of insulin-like growth factor 1 (IGF-I), most frequently caused by pituitary adenomas. Elevated GH and IGF-I levels results in wide range of somatic, cardiovascular, endocrine, metabolic, and gastrointestinal morbidities. Subcutaneous implantation of the GH-secreting GC cell line in rats leads to the formation of tumors. GC tumor-bearing rats develop characteristics that resemble human acromegaly including gigantism and visceromegaly. However, GC tumors remain poorly characterized at a molecular level. In the present work, we report a detailed histological and molecular characterization of GC tumors using immunohistochemistry, molecular biology and imaging techniques. GC tumors display histopathological and molecular features of human GH-producing tumors, including hormone production, cell architecture, senescence activation and alterations in cell cycle gene expression. Furthermore, GC tumors cells displayed sensitivity to somatostatin analogues, drugs that are currently used in the treatment of human GH-producing adenomas, thus supporting the GC tumor model as a translational tool to evaluate therapeutic agents. The information obtained would help to maximize the usefulness of the GC rat model for research and preclinical studies in GH-secreting tumors., D.A.C. was supported by the Nicolás Monardes program of the Andalusian Ministry of Health (C-0015-2014) and by a grant from the Andalusian Ministry of Science and Innovation (CTS-7478). A.S-M and A.L.C were supported by grants from the ISCIII-Subdirección General de Evaluación y Fomento de la Investigación co-funded with Fondos FEDER (PI12/0143 and PI13/02043, respectively) and the Andalusian Regional Government (CTS-444) and a grant from Pfizer Spain. R.L.C. was supported by a grant from Andalusian Ministry of Health (PI0302-2012). R.M.L. was supported by grants from Proyecto de Investigación en Salud (FIS) PI13-00651 (funded by Instituto de Salud Carlos III), CTS-1406, PI-0639-2012, BIO-0139 (funded by Junta de Andalucía) and by Ayuda Merck Serono 2013. J. P. C. was funded by a grant (BFU2013-43282-R) from Ministerio de Economía y Competitividad. CIBER is an initiative of Instituto de Salud Carlos III, Ministerio de Sanidad, Servicios Sociales e Igualdad, Spain. J.F.M.R. is supported by the “Sara Borrell” program from the Instituto de Salud Carlos III. R.M. Luque and J.P. Castaño have received grants and lecture fees from Ipsen and Novartis. E. Venegas-Moreno and A. Soto-Moreno received grants and lecture fees from Ipsen, Novartis and Pfizer. A. Leal-Cerro received grants from Novartis and Pfizer. David Cano received a grant from Novartis.

Summary Objective Somatostatin (SS) may not merely be inhibitory to GH secretion but, under appropriate temporal conditions, may act in a paradoxically positive manner to sensitize somatotroph responsiveness to GHRH. SS infusion withdrawal (SSIW) produces a rebound GH rise in humans and increases GHRH-induced GH release. Theoretically SSIW leaves the somatotroph cell in a situation of low endogenous SS. In Cushing's syndrome, GH secretion appears blunted to all stimuli. The mechanisms by which glucocorticoids impair GH secretion in Cushing's syndrome are unknown. There are no data evaluating GH responsiveness to SSIW plus GHRH in Cushing's syndrome patients. The aim of the present study was to evaluate the GH response to SSIW plus GHRH in a group of Cushing's syndrome patients, in order to further understand the deranged GH secretory mechanisms in Cushing's syndrome. Patients and Measurements Eight female patients with Cushing's syndrome were studied. As a control group, eight normal subjects of similar age and sex were studied. Three tests were done. On one day, SS intravenous (i.v.) infusion (500 µg for 0–90 min) was performed followed by placebo i.v. bolus at min 90 after SS withdrawal (SSIW). On another day, SS i.v. infusion (500 µg for 0–90 min) was performed followed by GHRH (100 µg) i.v. bolus at min 90 after SS withdrawal. On a third day, slow infusion of 150 mmol/l NaCl administration was performed followed by GHRH (100 µg) i.v. bolus at min 90 after the start of the infusion. Blood samples were taken at appropriate intervals for determination of GH. Results GHRH-induced GH secretion in normal subjects showed a mean peak of 15·4 ± 2·1 µg/l (conversion factor: 1 µg/l = 1·2 mUI/l). Normal control subjects had a mean peak of 3·3 ± 1·6 µg/l after SSIW-induced GH secretion. When GHRH was administered after SSIW there was increased GH secretion with a mean peak of 23·7 ± 4·2 µg/l significantly greater than the response after SSIW alone (P

Glial-derived neurotropic factor (GDNF) signaling is mediated through a 2-component system consisting of the so-called GDNF receptor-α (GFRα1), which binds to GDNF. This complex activates the tyrosine kinase receptor RET. In this paper we demonstrate GDNF, GFRα1, and RET mRNA and protein expression in the human anterior pituitary gland. Double immunohistochemistry of anterior pituitary sections showed GDNF immunoreactivity in more than 95% of somatotrophs and to a lesser extent in corticotrophs (20%); it was almost absent in the remaining cell types. Also, although more than 95% of somatotrophs were stained for RET, no positive immunostaining could be detected in other cell types. Furthermore, we have looked for GDNF and RET in human pituitary adenomas of various hormonal phenotypes. Strong positive immunostaining was found for c-RET in all of the GH-secreting adenomas screened as well as in 50% of ACTH-producing adenomas. Positive immunostaining for GDNF was found in all of the GH-secreting adenomas and in 10% of the corticotropinomas. Lastly, we found strong positive immunostaining for GFRα1 in 90% of the somatotropinomas and 50% of the corticotropinomas as well as in 1 of 8 prolactinomas and 1 of 13 nonfunctioning adenomas. All of the remaining pituitary tumors screened were negative for RET, GDNF, and GFRα1. This study indicates that GDNF may well be acting in the regulation of somatotroph cell growth and/or cell function in the normal human anterior pituitary gland. The expression of RET in all of the somatotropinomas and in 50% of the ACTH-producing tumors implies that GDNF and RET could be involved in the pathogenesis of pituitary tumors.

OBJECTIVES. Somatostatin (SS) may not merely be inhibitory to GH secretion but, under appropriate temporal conditions, may act in a paradoxically positive manner to sensitize somatotroph responsiveness to GH-releasing hormone (GHRH). SS infusion withdrawal (SSIW) produces a rebound GH rise in humans and increases GHRH-induced GH release. Theoretically, SSIW leaves the somatotroph cell in a situation of low endogenous SS. In obesity, there is markedly decreased GH secretion. In both children and adults, the greater the body mass index (BMI), the lower the GH response to provocative stimuli. It has been postulated that increased hypothalamic somatostatin secretion is the main mechanism responsible for the blunted GH secretion of obesity. There are no data evaluating GH responsiveness to SSIW plus GHRH in obese adults. The aim of the present study was to evaluate the GH response to SSIW plus GHRH in a group of control subjects and a group of obese patients. PATIENTS AND MEASUREMENTS. Seven obese patients (six female, one male) with a BMI of 36.1±7.7 kg/m2 were studied. As a control group, seven normal subjects (six female, one male) with a BMI of 20.3±0.9 kg/m2 were also studied. Two tests were performed. On one day, somatostatin (SS) i.v. infusion (500μg from 0-90 min) was performed followed by a placebo i.v. bolus 90 min after SS withdrawal (SSIW). On another day, SS i.v. infusion (500μg from 0-90 min) was performed followed by a GHRH (100μg) i.v. bolus 90 min after SS withdrawal. A second group of seven obese patients (six female, one male) with a BMI of 32.2±2.3 kg/m2 were studied. As a second control group, seven normal healthy subjects (six female, one male) with a BMI of 20.1±0.6 kg/m2 were also studied. On one day, saline infusion was performed followed by a placebo i.v. bolus at 90 min. On another day, saline infusion was performed followed by a GHRH (100μg) i.v. bolus at 90 min. Blood samples were taken at appropriate intervals for determination of GH. Serum GH was measured by chemiluminescent immunometric assay. Statistical analysis was performed by Wilcoxon and Mann-Whitney tests. RESULTS. GHRH-induced GH secretion in normal subjects showed a mean peak of 15.8±2.1 μg/l. Normal control subjects had a mean peak of 3.1±1.5 μg/l after SSIW-induced GH secretion. When GHRH was administered after SSIW there was an increased GH secretion with a mean peak of 23.3±4.4 μg/l, significantly greater than the response after SSIW alone (P < 0.05) and GHRH alone (P < 0.05). GHRH-induced GH secretion in obese patients was decreased with a mean peak of 3.9±1.5 μg/l. In obese patients, GH secretion after SSIW was markedly decreased with a mean peak of 1.0±0.4 μg/l. When GHRH was administered after SSIW, an increase in GH secretion was observed with a mean peak of 4.3±0.9 μg/l, significantly greater than SSIW alone (P < 0.05) but not GHRH alone (P = NS), and significantly less than in normal subjects (P < 0.05). CONCLUSIONS. This study demonstrates a significantly blunted peak GH response to somatostatin infusion withdrawal plus GHRH in obese patients compared to normal subjects. In this theoretical situation of decreased somatostatinergic tone, there is persistence of GH hyposecretion in obesity, suggesting the existence of multiple defects responsible for decreased GH secretion in obesity. We also found that in obese patients, in contrast to normal subjects, SSIW did not increase GHRH-induced GH secretion.

Growth and growth hormone (GH) secretion are blunted or severely impeded in chronic hypercortisolism and in patients with Cushing's syndrome. A mechanistic explanation for the effect however has yet to be provided. On the other hand, several properties of ghrelin, a new peptide recently identified as the endogenous ligand of the GH secretagogue receptor, are still largely unknown. The two aims of this study were to observe whether ghrelin-mediated GH secretion was altered, and to characterize the corticotropin (ACTH) and cortisol response to this new stimulus in patients with Cushing's disease. Ten patients with active Cushing's disease (6 harboring microadenomas and 4 with macroadenomas) and 10 sex- and age-matched controls were studied. Ghrelin was administered at a dose of 1 microg/kg i.v. and GH, ACTH and cortisol analyzed in duplicate. In control women, ghrelin induced GH secretion to levels of 74.4 +/- 12.8 microg/l, while chronic hypercortisolism severely reduced the ghrelin-mediated GH release in all patients with Cushing's disease (peak values 17.7 +/- 5.2 microg/l). The slightly, but significantly higher adiposity of patients vs. controls may have contributed to the effect, since a significant negative correlation (r = 0.639) was found between the amplitude of the GH peak and body mass index. In control women, ghrelin increased ACTH and cortisol levels, with peaks at 57.4 +/- 19.0 ng/l and 162 +/- 16 microg/l, respectively. This secretion was enhanced in Cushing's syndrome patients, with ACTH and cortisol values of 380.7 +/- 109.8 ng/l and 338 +/- 81 microg/l respectively, both significantly higher than in controls. In conclusion, ghrelin-induced GH secretion was severely blunted in patients with active Cushing's syndrome, in addition to a remarkable hyper-response in ACTH and cortisol secretion. These findings could have implications for the understanding of the physiology and physiopathology of interactions between GH and ACTH regulation.

We hypothesized that in nonectopic Cushing syndrome there is an insufficient activity of type II (renal) 11beta-hydroxysteroid dehydrogenase (11beta-HSD2) that is related to cortisol excess, rather than to corticotropin (adrenocorticotropic hormone [ACTH]) levels. We measured plasma ACTH and urinary-free cortisol (UFF), urinary-free cortisone (UFE), tetrahydrocortisol (UTHF), and tetrahydrocortisone (UTHE) in 24-h urine samples of 24 healthy subjects and 15 patients diagnosed with nonectopic Cushing syndrome. Then, in the group of patients, a new 24-h urine sample was collected after treatment with 800 mg daily of ketoconazole. The UFF/UFE and UTHF/UTHE ratios were calculated as an estimation of 11beta-HSD2 activity. The patients had an increase in both the UFF/UFE (19.95 +/- 10.3 vs 5.78 +/- 4.72 nmol/24 h; p0.0001) and UTHF/UTHE ratios (5.36 +/- 5.23 vs 1.39 +/- 0.95 nmol/24 h; p0.001). Both UFF/UFE and UTHF/UTHE ratios decreased after ketoconazole treatment (19.95 +/- 10.3 vs 12.2 +/- 6.9 nmol/24 h; p0.005; and 5.36 +/- 5.23 vs 1.62 vs 1.21 nmol/24 h; p0.001, respectively). The control subjects had a significant relationship between UFF and UFE (r = 0.70, p0.0001), and between UTHF and UTHE (r = 0.75, p0.0001) that did not exist in the patient group. After ketoconazole treatment, the decrease in cortisol excretion in the patient group allowed a positive and significant relation between UFF and UFE (r = 0.64, p0.01) and between UTHF and UTHE (r = 0.56, p0.05) to appear. There was not any significant relationship between either UFF/UFE or UTHF/UTHE ratios and plasma levels of ACTH.

The discovery of the adipocyte-produced hormone leptin has changed the field of obesity research and our understanding of energy homeostasis. It is now accepted that leptin is the afferent loop informing the hypothalamus about the states of fat stores, with hypothalamic efferents regulating appetite and energy expenditure. I addition, leptin has a role as a metabolic adaptator in overweight and fasting states. New and previously unsuspected neuroendocrine roles have emerged for leptin. Leptin participates in the expression of CRH in the hypothalamus, interacts at the adrenal level with ACTH, and is regulated by glucocorticoids. Since leptin and cortisol show an inverse circadian rhythm, it has suggested that a regulatory feedback is present. However glucocorticoids appears to play a modulatory, but not essential roles in generating leptin diurnal rhythm. Glucocortiocids act directly on the adipose tissue and increase leptin syntesis and secretion in humans. Leptin levels are markedly increased in Cushing's syndrome patients and in others pseudo-Cushing's syndrome states. Glucocorticoids appears to act as a key modulator of body weight and food intake, promoting leptin secretion by adipocytes, limiting central leptin induced effects and favoring those of the NPY. Furthermore the modulatory role of glucocorticoids could be altered in obesity, but the precise mode of action remains to be established. The relevance of this finding merits further studies.

Fibromyalgia (FM) is a painful syndrome of nonarticular origin, characterized by fatigue and widespread musculoskeletal pain, tiredness, and sleep disturbances, without any other objective findings on examination. Interestingly, some of the clinical features of FM resemble the ones described in the adult GH-deficiency syndrome. Furthermore, insulin-like growth factor (IGF)-1 levels are frequently reduced in patients with FM. To gain further insight into the mechanisms leading to dysregulation of the GH-IGF-1 axis in these patients, we assessed 24-h spontaneous GH secretion, GH responses to GHRH, and IGF-1 and IGF binding protein (BP)-3 levels before and after 4 days treatment with human (h)GH. We found that, in comparison with controls, patients with FM exhibited a marked decrease in spontaneous GH secretion as assessed by mean GH secretion (2.5 +/- 0.4 microg/L in controls vs. 1.2 +/- 0.1 microg/L in FM, P < 0.05), pulse height (4.7 +/- 0.8 microg/L in controls vs. 2.5 +/- 0.3 microg/L in FM, P < 0.05), and pulse area (4.7 +/- 1 min/mg x L in controls vs. 2.3 +/- 0.3 min/mg x L in FM, P < 0.05). In contrast, GH responses to GHRH (100 microg, i.v.) were similar in controls (mean peak, 13.5 +/- 2.5 microg/L) and in patients with FM (12.2 +/- 3 microg/L). Finally, treatment with hGH (2 IU, s.c. daily), over 4 days, led to a clear-cut increase in plasma IGF-1 and IGFBP-3 levels in patients with FM. In conclusion, our data show that patients with FM exhibited a marked decrease in spontaneous GH secretion, but normal pituitary responsiveness to exogenously administered GHRH, thus suggesting the existence of an alteration at the hypothalamic level in the neuroendocrine control of GH in these patients. Furthermore, our finding of increased IGF-1 and IGFBP-3 levels after GH treatment, over 4 days, opens up the possibility of testing the therapeutic potential of hGH in patients with FM.

Leptin is a hormone produced by the adipocytes to regulate food intake and energy expenditure at the hypothalamic level. It is commonly accepted that the main determinants of leptin secretion are the net amount of body fat and the mean size of adipocytes. On the contrary, important vectors of energy flux in the organism, such as food intake and energy expended on exercise, are not thought to be regulators of that secretion. To understand whether leptin is regulated by an acute energy expenditure such as strenuous exercise, 29 male athletes who had trained for marathon running were studied before and after a marathon run and compared with 22 nonobese, age-, sex-, and body mass index (BMI)-matched sedentary controls. Controls and marathon athletes showed no differences in BMI or fat-free mass. Marathon runners showed a strong reduction in total fat mass (6.2 +/- 0.4 kg; 9.1 +/- 0.5% of body fat) compared with controls (12.3 +/- 0.5 kg; 16.1 +/- 0.5% of body fat; P < 0.05). This difference in body composition was paralleled by a mean serum leptin level that in marathonians (2.9 +/- 0.2 micrograms/L) was significantly (P < 0.05) reduced compared with that in controls (5.1 +/- 0.6 micrograms/L). It is remarkable that the ratio of leptin per kg body fat, showed a very good agreement between the two groups, 0.40 +/- 0.04 microgram/L.kg for controls and 0.46 +/- 0.03 microgram/L.kg for marathonians. In the two groups, leptin was correlated with both body weight, BMI, and fat mass (P < 0.001). The marathon trajectory was the standard 42.195 km accomplished in an average time of 3 h, 17 min, 7 s, with a calculated energy expenditure of over 2800 Cal. After the marathon run, a water imbalance occurred, with a significant decrease in body weight and an increase in serum albumin. A significant (P < 0.05) reduction in leptin values was observed after the run (2.6 +/- 0.2 micrograms/L) compared with before (2.9 +/- 0.2 micrograms/L), which was more relevant considering the relative hemoconcentration. In conclusion, 1) compared with sedentary subjects, leptin levels are reduced in male marathon runners in parallel with the relevant reduction in total body fat; 2) expressed as a ratio of leptin per kg body fat, no differences were observed between marathonians and controls; and 3) after an energy expenditure of 2800 Cal in the marathon run, a reduction in leptin levels occurred. Strong changes in energy expenditure may regulate serum leptin levels in man.

~Division of Endocrinology, Hospita[ Xeral, Vigo, Spain, 2Division of Endocrinology, Hospital Virgen del Rocio, Seville, Spain, 3Department of Medicine, Faculty of Medicine and Complejo Hospitalario de Santiago, Santiago de Compostela University, Santiago de Compostela, Spain, 4Institute of Endocrinology, University Clinical Centre, Belgrade, Yugoslavia, 5Department of Pediatrics and 6Department of Physiology, Faculty of Medicine and Complejo Hospitalario de Santiago, Santiago de Compostela University, Santiago de Compostela, Spain

OBJECTIVE In patients with Cushing's syndrome, decreased growth hormone (GH) secretion is observed although the basic mechanism is not yet understood. A short-term hypocaloric diet is known to increase both spontaneous and GHRH-stimulated GH secretion in normal subjects. In order to gain further insight into the altered GH secretion in patients with Cushing's syndrome, we assessed the effect of a short-term hypocaloric diet on GH responses to GHRH in these patients. DESIGN Two GHRH tests (1 μg/kg i.v.) were performed, the first under basal conditions (normocaloric diet) and the second after a 3-day hypocaloric diet (650 cal/day). PATIENTS Six female patients with untreated Cushing's disease. MEASUREMENTS Plasma GH levels were measured by immunoradiometric assay. RESULTS GHRH-induced GH release was impaired in patients with Cushing's disease on a normal diet (mean peak 12.4 ± 6.4 mU/l, area under the curve (AUC) 744 ± 332 mU/l/120 min). Following a hypocaloric diet, GH responses to GHRH were markedly enhanced in the same group of patients (mean peak 46.2 ± 14.8 mU/l, AUC 3142 ± 1032 mU/l/120 min, P

The immune-inflammatory response as well as cerebral endothelial activation has been described after Traumatic Brain Injury (TBI). Although inflammation can have both beneficial and detrimental effects in TBI, the mechanisms underlying this dichotomy are mostly unknown. Moreover, emerging data indicates that chronic alterations produced after TBI are probably the result of systemic and persistent inflammation that activates immune response, culminating in the production of different specific auto antibodies against central nervous system antigens. In the previous study we demonstrated the production of anti-hnRNPK antibodies, belonging to Anti-Endothelial Cell Antibodies (AECA), in heart transplanted patients who developed Cardiac Allograft Vasculopathy (CAV). These antibodies could be produced in response to the vascular endothelial damage that is also present in TBI patients. In the current study we analyse the presence of AECA by Indirect Immunofluorescence assay (IFI) and anti-hnRNPK IgG antibodies by Enzyme-Linked Immunosorbent Assay (ELISA) in a cohort of 19 patients who suffered TBI. We detected a significant increase in the number of patients with AECA and anti-hnRNPK antibodies after TBI. Moreover, anti-hnRNPK antibody levels were also higher during follow-up, being the values obtained after TBI significantly higher than those detected at the time of trauma (p = 0.001). We also found that AECA and anti-hnRNPK antibodies were mostly present in the sera of patients with a worse outcome (p = 0.018 and p = 0.04 respectively). Taking into account, measuring these auto antibodies could be useful for evaluating endothelial injury and/or the outcome after TBI.

The biochemical diagnosis of individuals who are either deficient in growth hormone (GH) or who have alterations in the normal pattern of GH secretion is difficult. The uncertainty surrounding diagnosis reflects the lack of a thorough understanding of the physiology of GH secretion and of the hypothalamic hormones involved. At least three hormones are implicated: GH-releasing hormone (GHRH), somatostatin and the endogenous ligand of the GH secretagogue receptor, although the role that each plays in the release of GH is not clear from the available experimental evidence. In such a situation, most of the dynamic tests of GH secretory capacity in humans need to undergo a 'trial and error' process before being validated. The search for the 'gold standard' test of GH secretion is ongoing, and the combination of GHRH plus GH secretagogues will probably play an important role in future clinical diagnosis.

In Cushing’s syndrome, GH secretion is blocked with all the stimuli tested. It has been reported that the acute pharmacological reduction of free fatty acids (FFA) leads to an enhancement of GH secretion in normal subjects and in pathological conditions associated with reduced GH secretion. To understand if the elevated FFA levels of hypercortisolism may be responsible for the altered GH secretion, 14 patients with active Cushing’s syndrome underwent 2 paired tests with 100 μg iv of GHRH on 2 different occasions. In one test, they were pretreated with placebo and in the other one, with acipimox 250 mg po 4 h before, and 250 mg po 1 h before GHRH. The basal FFA levels (799 ± 57 mmol/L) were reduced by acipimox throughout the whole test (values under 240 ± 28 mmol/L). In the placebo pretreated group, GHRH-induced GH secretion was severely impeded, with a mean GH peak of 1.8 ± 0.3 μg/L and area under the curve of 121.3 ± 21.6 μg/L·120 min. All the patients showed a GHRH-mediated GH peak under 4 μg/L. Acute r...

To prospectively evaluate the effect of weight loss after bariatric surgery on microvascular function in morbidly obese patients with and without metabolic syndrome (MetS).A cohort of morbidly obese patients with and without MetS was studied before surgery and after 12 months of surgery. Healthy lean controls were also examined. Microvascular function was assessed by postocclusive reactive hyperemia (PORH) at forearm skin evaluated by laser Doppler flowmetry (LDF). Cutaneous vascular conductance (CVC) was calculated from laser-Doppler skin blood flow and blood pressure. Regression analysis was performed to assess the contribution of different clinical, metabolic and biochemical parameters to microvascular function.Before surgery, 62 obese patients, 39 with MetS and 23 without MetS, and 30 lean control subjects were analyzed. The absolute area under the hyperemic curve (AUC(H)) CVC of PORH was significantly decreased in obese patients compared with lean control subjects. One year after surgery, AUC(H) CVC significantly increased in patients free of MetS, including patients that had MetS before surgery. In contrast, AUC(H) CVC did not significantly change in patients in whom MetS persisted after surgery. Stepwise multivariate regression analysis showed that only changes in HDL cholesterol (HDL-C) and oxidized LDL (oxLDL) independently predicted improvement of AUC(H) after surgery. These two variables together accounted for 40.9% of the variability of change in AUC(H) CVC after surgery.Bariatric surgery could significantly improve microvascular dysfunction in obese patients, but only in patients free of MetS after surgery. Improvement of microvascular dysfunction is strictly associated to postoperative increase in HDL-C levels and decrease in oxLDL levels.

Patients with active untreated acromegaly show mild to moderate neurocognitive disorders that are associated to chronic exposure to growth hormone (GH) and insulin-like growth factor (IGF-I) hypersecretion. However, it is unknown whether these disorders improve after controlling GH/IGF-I hypersecretion. The aim of this study was to compare neurocognitive functions of patients who successfully underwent GH-secreting adenoma transsphenoidal surgery (cured patients) with patients with naive acromegaly. In addition, we wanted to determine the impact of different clinical and biochemical variables on neurocognitive status in patients with active disease and after long-term cure. A battery of six standardized neuropsychological tests assessed attention, memory and executive functioning. In addition, a quantitative electroencephalography with Low-Resolution Electromagnetic Tomography (LORETA) solution was performed to obtain information about the neurophysiological state of the patients. Neurocognitive data was compared to that of a healthy control group. Multiple linear regression analysis was also conducted using clinical and hormonal parameters to obtain a set of independent predictors of neurocognitive state before and after cure. Both groups of patients scored significantly poorer than the healthy controls on memory tests, especially those assessing visual and verbal recall. Patients with cured acromegaly did not obtain better cognitive measures than naïve patients. Furthermore memory deficits were associated with decreased beta activity in left medial temporal cortex in both groups of patients. Regression analysis showed longer duration of untreated acromegaly was associated with more severe neurocognitive complications, regardless of the diagnostic group, whereas GH levels at the time of assessment was related to neurocognitive outcome only in naïve patients. Longer duration of post-operative biochemical remission of acromegaly was associated with better neurocognitive state. Overall, this data suggests that the effects of chronic exposure to GH/IGF-I hypersecretion could have long-term effects on brain functions. © 2013 Martín-Rodríguez et al., Funding for this project was provided by an R&D grant from Novartis Oncology and the Plan Andaluz de Investigación (CTS-444). DAC was supported by the “Ramón y Cajal” program (RYC-2006-001071) of the Spanish Ministry of Science and Innovation.

The mammalian pancreas is densely innervated by both the sympathetic and parasympathetic nervous systems, which control exocrine and endocrine secretion. During embryonic development, neural crest cells migrating in a rostrocaudal direction populate the gut, giving rise to neural progenitor cells. Recent studies in mice have shown that neural crest cells enter the pancreatic epithelium at E11.5. However, the cues that guide the migration of neural progenitors into the pancreas are poorly defined. In this study we identify glial cell line-derived neurotrophic factor (GDNF) as a key player in this process. GDNF displays a dynamic expression pattern during embryonic development that parallels the chronology of migration and differentiation of neural crest derivatives in the pancreas. Conditional inactivation of Gdnf in the pancreatic epithelium results in a dramatic loss of neuronal and glial cells and in reduced parasympathetic innervation in the pancreas. Importantly, the innervation of other regions of the gut remains unaffected. Analysis of Gdnf mutant mouse embryos and ex vivo experiments indicate that GDNF produced in the pancreas acts as a neurotrophic factor for gut-resident neural progenitor cells. Our data further show that exogenous GDNF promotes the proliferation of pancreatic progenitor cells in organ culture. In summary, our results point to GDNF as crucial for the development of the intrinsic innervation of the pancreas., D.A.C. was supported by the Ramón y Cajal program [RYC-2006-001071] and by grants from the Spanish Ministry of Science and Innovation [SAF2008-02469 and SAF2011-26805] and the Andalusian Regional Ministry of Health [PI-0250/2008]. A.L.-C. was supported by grants from the Andalusian Regional Government [P08-CVI-3727 and CTS-444]. A.P. was supported by grants from the Spanish Ministry of Science and Innovation [SAF2009-06977] and the Andalusian Regional Government [CTS-3560]. J.L.-B. was supported by the Botín Foundation, CIBERNED, and the Spanish Ministries of Science (SAF Program) and Health.

Leal-Cerro A, Garcia E, Astorga R, Casanueva FF, Dieguez C. Growth hormone (GH) responses to the combined administration of GH-releasing hormone plus GH-releasing peptide 6 in adults with GH deficiency. Eur J Endocrinol 1995;132:712–5. ISSN 0804–4643 In recent years the health problems of adults with growth hormone deficiency (GHD) and the benefits of GH replacement therapy have received considerable attention. However, the reliability of conventional GH tests in the assessment of pituitary GH reserve in this group of patients is still controversial. In this study, we assessed GH secretion after the combined administration of GH-releasing hormone (GHRH) (1 μg/kg iv) and GH-releasing peptide 6 (GHRP-6, 1 μg/kg iv) in adult patients diagnosed with GHD by conventional GH testing, and correlate this response with insulin-like growth factor I levels. Twenty-one subjects (13 male, 8 female) with long-standing diagnosis of GHD aged 21–54 years were studied. In 13 subjects GH responses to GHRH plus GHRP-6 were markedly reduced (peak GH response C Dieguez, PO Box 563, 15700 Santiago de Compostela, Spain

Summary OBJECTIVE In patients with Cushing's syndrome there is a blunted OH response to all types of stimuli. Although Inferential data point towards a direct perturbation in the pituitary exerted by glucocorticoids, the bask mechanism is unknown. His-d-TRP-ALA-TRP-d-Phe-Lys-NH2 (GHRP-6) is a synthetic hexapeptlde which releases GH by a direct pituitary effect through receptors other than GHRH receptors. Furthermore, the combined administration of GHRH and GHRP-6 is able to induce a large OH discharge even in some pathological states such as obesity, associated with GH blockade. To gain further insight into the disrupted mechanisms of GH secretion, Cushing's syndrome patients were challenged with either GHRH, GHRP-6 or GHRH together with GHRP-6. A group of normal subjects was included for control purposes. DESIGN Three different tests were undertaken: (a) GHRH 100 μg I.v.; (b) GHRP-6 100 μg I.v. and (c) GHRH plus GHRP-6 100 μg I.v. of each; administered to each subject on different days, at least 4 days apart. PATIENTS Ten patients (8 women, 2 men) with untreated Cushing's syndrome, 9 Cushing's disease and 1 adrenal adenoma. Five healthy volunteers (3 women, 2 men) of similar ages served as a control group. MEASUREMENTS Plasma OH levels were measured by immunoradiometric assay. RESULTS The areas under the curve (AUC) of OH secretion (mean ± SEM In μ/1/120 mi) in the control subjects after each test were: GHRH, 1420 ± 330; GHRP-6, 2278 ± 290 and GHRH plus GHRP-6,7332 ± 592 (P < 0·05 vs each compound alone). The AUCs for Cushing's syndrome patients were: GHRH, 248 ± 165; GHRP-6 530 ±170 and for GHRH plus GHRP-6, 870 ± 258 (P < 0·05 vs GHRH alone). After the combined stimulus only one out of the ten patients with hypercortisolism showed a GH peak over 20 μ/l, while ail the controls had a peak over 04mU/l. CONCLUSIONS GHRP-6 induced OH secretion as well as the OH discharge elicited by GHRH and GHRP-6 are considerably reduced in Cushing's syndrome patients. This suggests that the main impairment of GH secretion in that pathological state resides at pituitary level.