31 research outputs found
Role of Estrogen and Estrogen Receptor in GH-Secreting Adenomas
Acromegaly is a rare disease with several systemic complications that may lead to increased overall morbidity and mortality. Despite several available treatments, ranging from transsphenoidal resection of GH-producing adenomas to different medical therapies, complete hormonal control is not achieved in some cases. Some decades ago, estrogens were first used to treat acromegaly, resulting in a significant decrease in IGF1 levels. However, due to the consequent side effects of the high dose utilized, this treatment was later abandoned. The evidence that estrogens are able to blunt GH activity also derives from the evidence that women with GH deficiency taking oral estro-progestins pills need higher doses of GH replacement therapy. In recent years, the role of estrogens and Selective Estrogens Receptor Modulators (SERMs) in acromegaly treatment has been re-evaluated, especially considering poor control of the disease under first- and second-line medical treatment. In this review, we analyze the state of the art concerning the impact of estrogen and SERMs on the GH/IGF1 axis, focusing on molecular pathways and the possible implications for acromegaly treatment
A novel RUNX1 mutation with ANKRD26 dysregulation is related to thrombocytopenia in a sporadic form of myelodysplastic syndrome
Aging is associated with a higher risk of developing malignant diseases, including myelodysplastic syndromes, clonal disorders characterised by chronic cytopenias (anaemia, neutropenia and thrombocytopenia) and abnormal cellular maturation. Myelodysplastic syndromes arising in older subjects are influenced by combinations of acquired somatic genetic lesions driving evolution from clonal haematopoiesis to myelodysplastic syndromes and from myelodysplastic syndromes to acute leukaemia. A different pattern of mutations has been identified in a small subset of myelodysplastic syndromes arising in young patients with familial syndromes. In particular, dysregulation of ANKRD26, RUNX1 and ETV6 genes plays a role in familial thrombocytopenia with predisposition to myelodysplastic syndromes and acute leukaemia. Whether these genes affect thrombopoiesis in sporadic myelodysplastic syndrome with thrombocytopenia is still undefined. Thirty-one myelodysplastic syndromes subjects and 27 controls subjects were investigated. Genomic DNA was used for mutation screening (ETV6, RUNX1, 5âČUTR ANKRD26 genes). Functional studies were performed in the MEG-01-akaryoblastic cell line. We found four novel variants of RUNX1 gene, all in elderly myelodysplastic syndromes subjects with thrombocytopenia. Functional studies of the variant p.Pro103Arg showed no changes in RUNX1 expression, but the variant was associated with deregulated high transcriptional activity of ANKRD26 in MEG-01 cells. RUNX1 variant p.Pro103Arg was also associated with increased viability and reduced apoptosis of MEG-01, as well as impaired platelet production. Our findings are consistent with dysregulation of ANKRD26 in RUNX1 haploinsufficiency. Lack of repression of ANKRD26 expression may contribute to thrombocytopenia of subjects with sporadic myelodysplastic syndromes
Paradoxical GH increase after oral glucose load in subjects with and without acromegaly
Objective: A paradoxical GH rise after the glucose load (GH-Par) is described in about one-third of acromegalic patients. Here, we evaluated the GH profile in subjects with and without acromegaly aiming to refine the definition of GH-Par. Design: Observational caseâcontrol study. Methods: Our cohort consisted of 60 acromegalic patients, and two groups of subjects presenting suppressed GH (< 0.4 ”g/L) and high (non-acroâIGFâ1, n = 116) or normal IGF-1 levels (non-acro, n = 55). The distribution of GH peaks â„ 120% from baseline, insulin, and glucose levels were evaluated over a 180-min time interval after glucose intake. Results: A similar proportion of subjects in all three groups shows a GH ratio of â„ 120% starting from 120 min. Re-considering the definition of paradoxical increase of GH within 90 min, we observed that the prevalence of GH peaks â„ 120% was higher in acromegaly than in non-acroâIGFâ1 and non-acro (respectively 42%, 16%, and 7%, both p < 0.001). In patients without GH-Par, a late GH rebound was observed in the second part of the curve. Higher glucose peak (p = 0.038), slower decline after load, 20% higher glucose exposure (p = 0.015), and a higher prevalence of diabetes (p = 0.003) characterized acromegalic patients with GH-Par (with respect to those without). Conclusions: GH-Par response may be defined as a 20% increase in the first 90 min after glucose challenge. GH-Par, common in acromegaly and associated with an increased prevalence of glucose metabolism abnormalities, is found also in a subset of non-acromegalic subjects with high IGF-1 levels, suggesting its possible involvement in the early phase of the disease
Clinical presentation and management of acromegaly in elderly patients
Background and aim: Acromegaly is a rare disease with a peak of incidence in early adulthood. However, enhanced awareness of this disease, combined with wide availability of magnetic resonance imaging (MRI), has increased the diagnosis of forms with mild presentation, especially in elderly patients. Moreover, due to increased life expectancy and proactive individualized treatment, patients with early-onset acromegaly are today aging. The aim of our study was to describe our cohort of elderly patients with acromegaly. Materials and methods: This is a cross-sectional retrospective study of 96 outpatients. Clinical, endocrine, treatment, and follow-up data were collected using the electronic database of the University Hospital of Padova, Italy. Results: We diagnosed acromegaly in 13 patients, aged 6565\ua0years, presenting with relatively small adenomas and low IGF-1 secretion. Among them, 11 patients were initially treated with medical therapy and half normalized hormonal levels after 6\ua0months without undergoing neurosurgery (TNS). Remission was achieved after TNS in three out of four patients (primary TNS in two); ten patients presented controlled acromegaly at the last visit. Acromegaly-related comorbidities (colon polyps, thyroid cancer, adrenal incidentaloma, hypertension, and bone disease) were more prevalent in patients who had an early diagnosis (31 patients, characterized by a longer follow-up of 24\ua0years) than in those diagnosed aged 6565\ua0years (5\ua0years of follow-up). Conclusions: Elderly acromegalic patients are not uncommon. Primary medical therapy is a reasonable option and is effectively used, while the rate of surgical success is not reduced. A careful cost-benefit balance is suggested. Disease-specific comorbidities are more prevalent in acromegalic patients with a longer follow-up rather than in those diagnosed aged 6565\ua0years
A Novel Mutation in the Upstream Open Reading Frame of the CDKN1B Gene Causes a MEN4 Phenotype
PubMed ID: 23555276This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited
Incretin Response to Mixed Meal Challenge in Active Cushingâs Disease and after Pasireotide Therapy
Cushingâs disease (CD) causes diabetes mellitus (DM) through different mechanisms in a significant proportion of patients. Glucose metabolism has rarely been assessed with appropriate testing in CD; we aimed to evaluate hormonal response to a mixed meal tolerance test (MMTT) in CD patients and analyzed the effect of pasireotide (PAS) on glucose homeostasis. To assess gastro-enteroâpancreatic hormones response in diabetic (DM+) and nonâdiabetic (DMâ) patients, 26 patients with CD underwent an MMTT. Ten patients were submitted to a second MMTT after two months of PAS 600 ÎŒg twice daily. The DM+ group had significantly higher BMI, waist circumference, glycemia, HbA1c, ACTH levels and insulin resistance indexes than DMâ (p < 0.05). Moreover, DM+ patients exhibited increased Câpeptide (p = 0.004) and glucose area under the curve (AUC) (p = 0.021) during MMTT, with a blunted insulinotropic peptide (GIP) response (p = 0.035). Glucagon levels were similar in both groups, showing a quick rise after meals. No difference in estimated insulin secretion and insulin:glucagon ratio was found. After two months, PAS induced an increase in both fasting glycemia and HbA1c compared to baseline (p < 0.05). However, this glucose trend after meal did not worsen despite the blunted insulin and Câpeptide response to MMTT. After PAS treatment, patients exhibited reduced insulin secretion (p = 0.005) and resistance (p = 0.007) indexes. Conversely, glucagon did not change with a consequent impairment of insulin:glucagon ratio (p = 0.009). No significant differences were observed in incretins basal and mealâinduced levels. Insulin resistance confirmed its pivotal role in glucocorticoidâinduced DM. A blunted GIP response to MMTT in the DM+ group might suggest a potential inhibitory role of hypercortisolism on enteropancreatic axis. As expected, PAS reduced insulin secretion but also induced an improvement in insulin sensitivity as a result of cortisol reduction. No differences in incretin response to MMTT were recorded during PAS therapy. The discrepancy between insulin and glucagon trends while on PAS may be an important pathophysiological mechanism in this iatrogenic DM; hence restoring insulin:glucagon ratio by either enhancing insulin secretion or reducing glucagon tone can be a potential therapeutic target
Diagnostic Accuracy of CT Texture Analysis in Adrenal Masses: A Systematic Review
Adrenal incidentalomas (AIs) are incidentally discovered adrenal neoplasms. Overt endocrine secretion (glucocorticoids, mineralocorticoids, and catecholamines) and malignancy (primary or metastatic disease) are assessed at baseline evaluation. Size, lipid content, and washout charac-terise benign AIs (respectively, <4 cm, <10 Hounsfield unit, and rapid release); nonetheless, 30% of adrenal lesions are not correctly indicated. Recently, image-based texture analysis from computed tomography (CT) may be useful to assess the behaviour of indeterminate adrenal lesions. We performed a systematic review to provide the state-of-the-art of texture analysis in patients with AI. We considered 9 papers (from 70 selected), with a median of 125 patients (range 20â356). Histological confirmation was the most used criteria to differentiate benign from the malignant adrenal mass. Unenhanced or contrast-enhanced data were available in all papers; TexRAD and PyRadiomics were the most used software. Four papers analysed the whole volume, and five considered a region of interest. Different texture features were reported, considering first-and second-order statistics. The pooled median area under the ROC curve in all studies was 0.85, depicting a high diagnostic accuracy, up to 93% in differentiating adrenal adenoma from adrenocortical carcinomas. Despite heterogeneous methodology, texture analysis is a promising diagnostic tool in the first assessment of patients with adrenal lesions
The (193-209) 17-residues peptide of bovine b-casein is transported through Caco-2 monolayer
Although the bioavailability of large peptides with biological activity is of great interest, the intestinal transport has been described for peptides up to only nine residues. \u3b2-casein (\u3b2-CN, 193-209) is a long and hydrophobic peptide composed of 17 amino acid residues (molecular mass 1881 Da) with immunomodulatory activity. The present work examined the transport of the \u3b2-CN (193-209) peptide across Caco-2 cell monolayer. In addition, we evaluated the possible routes of the \u3b2-CN (193-209) peptide transport, using selective inhibitors of the different routes for peptide transfer through the intestinal barrier. The results showed that the \u3b2-CN (193-209) peptide resisted the action of brush-border membrane peptidases, and that it was transported through the Caco-2 cell monolayer. The main route involved in transepithelial transport of the \u3b2-CN (193-209) peptide was transcytosis via internalized vesicles, although the paracellular transport via tight-junctions could not be excluded. Our results demonstrated the transport of an intact long-chain bioactive peptide in an in vitro model of intestinal epithelium, as an important step to prove the evidence for bioavailability of this peptide
Is pasireotide-induced diabetes mellitus predictable? A pilot study on the effect of a single dose of pasireotide on glucose homeostasis
Introduction: Pasireotide (PAS) is an effective treatment for Cushing\u2019s disease (CD) but its use is burdened by an associated high incidence of diabetes mellitus (DM). The aim of this study was to examine the effect of a single subcutaneous injection of PAS on glucose metabolism in CD, and to identify predictors of DM onset. Methods: Fifteen patients with CD (13 females, 2 males; median age 43 years [IQR 34\u201350]) were submitted to an acute PAS test (600 \ub5g s.c.), measuring glucose, insulin, C-peptide, GIP, glucagon, GLP-1, ACTH, and cortisol at the baseline and every 30 min for 2 h. Then they were treated twice daily with PAS 600 \ub5g, and followed up with clinical and hormone assessments for a median of 6 months [2\u201313]. Results: PAS prompted a significant decrease in all hormonal parameters considered except for glycemia, which increased (as expected), reaching the highest value at 120\u2032 (p 34.5 mmol/mol, and a glucose peak after PAS administration > 9 mmol/L. CD patients with these features given PAS therapy should therefore be monitored more carefully