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Open access

Zhiwei Zhang, Hui Zhao, and Aixia Wang

Background: Gestational diabetes mellitus (GDM) has a high incidence rate among pregnant women. The objective of the study was to assess the effect of plant-derived oleuropein in attenuating inflammatory and oxidative stress of GDM.

Methods: Oleuropein was administered to GDM mice at the doses of 5 or 10 mg/kg/day. Body weight, blood glucose, insulin and hepatic glycogen levels were recorded. To evaluate the effect of oleuropein in reducing oxidative stress, enzyme-linked immunosorbent assay (ELISA) was used to measure the hepatic oxidative stress markers. The inflammation levels of GDM mice were evaluated by measuring serum levels of IL-6 and TNF-α by ELISA, and mRNA levels of IL-1β, TNF-α and IL-6 by real-time PCR (RT-PCR). The AMP-activated protein kinase (AMPK) signaling pathway was assessed by Western blot. Gestational outcome was analyzed through comparing litter size and birth weight.

Results: Oleuropein attenuated the elevated body weight of GDM mice, and efficiently reduced blood glucose, insulin and hepatic glycogen levels. Oxidative stress and inflammation were alleviated by oleuropein treatment. The AMPK signaling was activated by oleuropein in GDM mice. Gestational outcome was markedly improved by oleuropein treatment.

Conclusions: Our study suggests that oleuropein is effective in alleviating symptoms of GDM and improving gestational outcome in the mouse model. This effect is achieved by attenuating oxidative stress and inflammation, which is mediated by the activation of the AMPK signaling pathway.

Open access

Lasse Oinonen, Antti Tikkakoski, Jenni Koskela, Arttu Eräranta, Mika Kähönen, Onni Niemelä, Jukka Mustonen, and Ilkka Pörsti

Parathyroid hormone has been related with the risk of hypertension, but the matter remains controversial. We examined the association of parathyroid hormone with central blood pressure and its determinants in 622 normotensive or never-treated hypertensive subjects aged 19-72 years without diabetes, cardiovascular or renal disease, or cardiovascular medications. The methods were whole-body impedance cardiography and analyses of pulse wave and heart rate variability. Cardiovascular function was examined in sex-specific tertiles of plasma parathyroid hormone (mean concentrations 3.0, 4.3 and 6.5 pmol/l, respectively) during head-up tilt. Explanatory factors for haemodynamics were further investigated using linear regression analyses. Mean age was 45.0 (SD 11.7) years, body mass index 26.8 (4.4) kg/m2, seated office blood pressure 141/90 (21/12) mmHg, and 309 subjects (49.7%) were male. Only five participants had elevated plasma parathyroid hormone and calcium concentrations. Highest tertile of parathyroid hormone presented with higher supine and upright aortic diastolic blood pressure (p<0.01) and augmentation index (p<0.01), and higher upright systemic vascular resistance (p<0.05) than the lowest tertile. The tertiles did not present with differences in pulse wave velocity, cardiac output, or measures of heart rate variability. In linear regression analyses, parathyroid hormone was an independent explanatory factor for aortic systolic (p=0.005) and diastolic (p=0.002) blood pressure, augmentation index (p=0.002), and systemic vascular resistance (p=0.031). To conclude, parathyroid hormone was directly related to central blood pressure, wave reflection, and systemic vascular resistance in subjects without cardiovascular comorbidities and medications. Thus, parathyroid hormone may play a role in the pathophysiology of primary hypertension.

Open access

Serena Martinelli, Mario Maggi, and Elena Rapizzi

Pheochromocytomas/paragangliomas (PPGLs) are rare neuroendocrine tumours linked to more than 15 susceptibility genes. PPGLs present with very different genotype/phenotype correlations. Certainly, depending on the mutated gene, and the activated intracellular signalling pathways, as well as their metastatic potential, each tumour is immensely different. One of the major challenges in in vitro research, whatever the study field, is to choose the best cellular model for that study. Unfortunately, most of the time there is not ‘a best’ cell model. Thus, in order to avoid observations that could be related to and/or dependent on a specific cell line, researchers often perform the same experiments using different cell lines simultaneously. The situation is even more complicated when there are only very few cell models obtained in different species for a disease. This is the case for PPGLs. In this review, we will describe the characteristics of the different cell lines and of mouse models, trying to understand if there is one that is more appropriate to use, depending on which aspect of the tumours one is trying to investigate.

Open access

Marta Araujo-Castro, Héctor Pian, Ignacio Ruz-Caracuel, Alberto Acitores Cancela, Eider Pascual-Corrales, and Víctor Rodríguez Berrocal

Purpose: To evaluate whether pre-surgical treatment using long-acting somatostatin receptor ligands (SRL) may change pituitary tumor consistency and improve surgical outcome in GH-secreting pituitary macroadenomas.

Methods: Retrospective study of 40 patients with GH-secreting pituitary macroadenomas operated for the first time by endoscopic transsphenoidal approach. Tumor consistency was evaluated intraoperatively and then correlated with histopathological fibrosis parameters and surgical outcomes. Surgical remission was reported based on the 2010 criteria.

Results: The mean tumor size of GH-secreting macroadenomas was of 16.9±8.2mm and 25 were invasive pituitary adenomas (PAs). Presurgical treatment with long-acting SRL was performed in 17 patients (11 lanreotide, 6 octreotide).

The cure rate was higher in those patients pre-treated with monthly doses ≥30mg of octreotide or ≥90mg of lanreotide than in those treated with lower doses or untreated (8/11 vs 11/29, P=0.049). However, although the proportion of soft tumors increased as higher doses of SRL were considered in the pre-treated group, no statistical significance was reached, even when the highest approved monthly doses were used (6/6 vs 23/34, P=0.102). Moreover, we found that the remission rate was similar between fibrous and soft tumors (P=0.873) and also of surgical complications (P=0.859), despite of the higher prevalence of Knosp>2 (P=0.035) and very large PA (P=0.025) in fibrous tumors than in soft tumors.

Conclusions: Although presurgical treatment with high doses of SRL was associated with a 2.2-fold greater chance of surgical remission, this benefit was not related with changes in tumor consistency induced by the presurgical treatment.

Open access

Mônica R Gadelha, Feng Gu, Marcello D Bronstein, Thierry C Brue, Maria Fleseriu, Ilan Shimon, Aart J van der Lely, Shoba Ravichandran, Albert Kandra, Alberto M Pedroncelli, and Annamaria A L Colao

Pasireotide, a multireceptor-targeted somatostatin analog with highest affinity for somatostatin receptor subtype (SST) 5, has demonstrated superior efficacy over the SST2-preferential somatostatin analogs octreotide and lanreotide. The safety profile is similar to those of octreotide and lanreotide, except for a higher frequency and degree of hyperglycemia. This analysis investigated baseline characteristics and occurrence and management of hyperglycemia during pasireotide treatment in patients with acromegaly treated in two prospective clinical studies, SOM230C2305 (C2305) and SOM230C2402 (C2402; PAOLA). One hundred and seventy-eight patients naïve to medical therapy at baseline (C2305) and 125 uncontrolled on first-generation somatostatin analogs at baseline (C2402) received long-acting pasireotide in these studies. Of patients treated with pasireotide in studies C2305 and C2402, respectively, 75.3 (134/178) and 65.6% (82/125) developed hyperglycemia or experienced worsening of existing hyperglycemia. Occurrence of hyperglycemia during pasireotide treatment was less frequent in patients with lower age (<40 years, C2402; <30 years, C2305), normal glucose tolerance, and no history of hypertension or dyslipidemia at baseline. Thirteen (4%) patients discontinued pasireotide because of hyperglycemia-related adverse events. Metformin alone or in combination with other oral antidiabetic medications controlled elevations in glucose levels in most pasireotide-treated patients; 78% of C2305 patients and 73 (pasireotide 40 mg) and 60% (pasireotide 60 mg) of C2402 patients achieved the ADA/EASD goal of HbA1c <7% (<53 mmol/mol) at the end of the core phase. Not all patients develop hyperglycemia, and it is reversible upon pasireotide withdrawal. Close monitoring, patient education and prompt action remain key elements in addressing hyperglycemia during pasireotide treatment.

Open access

Cecília Cristelo, Alexandra Machado, Bruno Sarmento, and Francisco Miguel Gama

Type 1 diabetes has increasingly greater incidence and prevalence with no cure available. Vitamin D supplementation is well documented to reduce the risk of developing type 1 diabetes. Being involved in the modulation of cathelicidin expression, the question whether cathelicidin may be one of the underlying cause arises. Cathelicidin has been implicated in both the development and the protection against type 1 diabetes by mediating the interplay between the gut microbiome, the immune system and β cell function. While its potential on type 1 diabetes treatment seems high, the understanding of its effects is still limited. This review aims to contribute to a more comprehensive understanding of the potential of vitamin D and cathelicidin as adjuvants in type 1 diabetes therapy.

Open access

Jose M Garcia, Beverly M. K. Biller, Marta Korbonits, Vera Popovic, Anton Luger, Christian J Strasburger, Philippe Chanson, Ronald Swerdloff, Christina Wang, Rosa Rosanna Fleming, Fredric Cohen, Nicola Ammer, Gilbert Mueller, Nicky Kelepouris, Frank Strobl, Vlady Ostrow, and Kevin Cj Yuen

Objective: The macimorelin test is approved for the diagnosis of adult growth hormone deficiency (AGHD) based on its efficacy vs the insulin tolerance test (ITT). Macimorelin has a significant advantage over ITT in avoiding hypoglycemia. Analyses were conducted to determine whether macimorelin performance is affected by age, body mass index (BMI), or sex, and evaluate its performance vs ITT over a range of GH cutpoints.

Design: Post hoc analyses of data from a previous randomized phase 3 study included participants aged 18-66 years with BMI <37 kg/m2 and high (Group A), intermediate (Group B), or low (Group C) likelihood for AGHD based on pituitary history, and matched controls (Group D).

Methods: Probability of AGHD was estimated using unadjusted, age-adjusted, BMI-adjusted, and sex-adjusted logistic models. Area under the curve (AUC) of the estimated receiver operating characteristic (ROC) curve (range, 0-1; 1=perfect) was compared for adjusted vs unadjusted models. Separate analyses evaluated agreement, sensitivity, and specificity for macimorelin and ITT using cutpoints of 2.8, 4.0, 5.1, and 6.5 ng/mL.

Results: For participants in Group A (n=41) and Group D (n=29), unadjusted, age-adjusted, BMI-adjusted, and sex-adjusted models had ROC AUCs (95% CIs) of 0.9924 (0.9807-1), 0.9924 (0.9807-1), 0.9916 (0.9786-1), and 0.9950 (0.9861-1), respectively.

Conclusions: Macimorelin performance was not meaningfully affected by age, BMI, or sex, indicating robustness for AGHD diagnosis. Of the 4 GH cutpoints evaluated, the cutpoint of 5.1 ng/mL provided maximal specificity (96%) and high sensitivity (92%) and was in good overall agreement with the ITT at the same cutpoint (87%).

Open access

Jessica S Jarmasz, Yan Jin, Hana Vakili, and Peter A Cattini

Human (h) growth hormone (GH) production studies are largely limited to effects on secretion. How pituitary hGH gene (hGH-N/GH1) expression is regulated is important in our understanding of the role hGH plays in physiology and disease. Here we assess for the first time the effect of sleep deprivation (SD) and high-fat diet (HFD) on hGH-N expression in vivo using partially humanized 171hGH/CS transgenic (TG) mice, and attempted to elucidate a role for DNA methylation. Activation of hGH-N expression requires interactions between promoter and upstream locus control region (LCR) sequences including pituitary-specific hypersensitive site (HS) I/II. Both SD and diet affect hGH secretion, but the effect of SD on hGH-N expression is unknown. Mice fed a HFD or regular chow diet for 3 days underwent SD (or no SD) for 6 h at Zeitgeber time (ZT) 3. Serum and pituitaries were assessed over 24 h at 6-h intervals beginning at ZT 14. SD and HFD caused significant changes in serum corticosterone and insulin, as well as hGH and circadian clock-related gene RNA levels. No clear association between DNA methylation and the negative effects of SD or diet on hGH RNA levels was observed. However, a correlation with increased methylation at a CpG (cytosine paired with a guanine) in a putative E-box within the hGH LCR HS II was suggested in situ. Methylation at this site also increased BMAL1/CLOCK-related nuclear protein binding in vitro. These observations support an effect of SD on hGH synthesis at the level of gene expression.

Open access

Enora Le Roux, Florence Menesguen, Isabelle Tejedor, Marc Popelier, Marine Halbron, Pauline Faucher, Sabine Malivoir, Graziella Pinto, Juliane Leger, Stephane Hatem, Michel Polak, Christine Poitou, and Philippe Touraine

Objective. The transition period between paediatric and adult medicine is associated with poor patient outcomes and important numbers of patients lost to follow up. Describe the cohort of patients in adult care who benefit from a new transition program based on case management approach.

Design. A longitudinal study was led since September 2016 in a French University Hospital.

Methods. Patients with any endocrine or metabolic disease diagnosed during childhood and transferred to adult care were included. The transition program includes 3 steps based on case management: liaising with paediatric services, personalising care pathways, liaising with structures outside hospital (General practitioner, educational and social sector).

Results. The cohort included 500 patients with malignant brain tumour (n=56 (11%)), obesity (n=55 (11%)), type 1 diabetes (n=54 (11%)), or other disease (n=335 (67%)). They were aged 19 in median at transfer, sex ratio: 0.5. At 21 months of follow-up in median, 439 (88%) have regular follow-up in or outside the hospital, 47 (9%) have irregular follow-up (absence at the last appointment or no appointment scheduled within the time recommended), 4 stopped care on the doctor's advice, 4 died, 3 moved, 3 refused care. The program involved 9,615 case management acts, 7% of patients required more than 50 acts. Patients who required most of support are usually affected by a neuro-cognitive disorder and have social issues.

Conclusions. The case manager addresses the complex needs of patients. With time, the cohort will provide unprecedented long-term results of patients with various conditions who went through transition.

Open access

Sondra O'Callaghan and Hanford Yau

Palliation of symptoms related to malignancy-associated hypercalcemia (MAH) is essential and clinically meaningful for patients, given the continued poor prognosis, with high morbidity and mortality associated with this disease process. Historically, agents have been temporizing, having no impact on patient morbidity nor survival. We suggest that cinacalcet can be an efficacious agent to be taken orally, reducing patients’ time in the hospital/clinic settings. It is well-tolerated and maintains serum calcium levels in the normal range, while targeted cancer treatments can be employed. This has a direct, major impact on morbidity. Maintaining eucalcemia can increase quality of life, while allowing targeted therapies time to improve survival. Given that our case (and others) showed calcium reduction in MAH, there is promising evidence that cinacalcet can be more widely employed in this setting. Future consideration should be given to studies addressing the efficacy of cinacalcet in calcium normalization, improvement of quality of life, and impact on survival in patients with MAH. Though the exact mechanism of action for cinacalcet’s reduction in calcium in this setting is not currently known, we can still afford patients the possible benefit from it.