Effectiveness of oral semaglutide on glucose control and body weight up to 18 months: a multicenter retrospective real-world study.

AIM: Oral semaglutide, an innovative orally administered GLP-1 receptor agonist for type 2 diabetes (T2D) management was herein evaluated for its effectiveness in a multi-center retrospective real-world study. METHODS: We included new-users of oral semaglutide from 18 specialist care centres and collected retrospective data on baseline clinical characteristics. Updated values of HbA1c and body weight were analyzed using the mixed model for repeated measures. RESULTS: The study included 166 individuals with T2D, predominantly men (64.5%), with a mean age of 64.4 years and a mean diabetes duration of 10.1 years. In the majority of patients (68.3%) oral semaglutide was used as a second-line drug, mostly with metformin. At baseline, mean BMI was 28.9 kg/m2 and HbA1c was 7.5%. During the 18-month observation period, oral semaglutide demonstrated significant reductions in HbA1c, with a maximum change of - 0.9%, and 42.1% of patients achieved HbA1c values below 7.0%. Additionally, there was a substantial reduction in body weight, with an estimated change of - 3.4 kg at 18 months, and 30.3% of patients experienced a 5% or greater reduction in baseline body weight. Only 24.2% of patients reached the 14 mg dose. Subgroup analysis revealed that baseline HbA1c > 7%, persistence on drug, not being on a prior therapy with DPP-4 inhibitors, and loosing 5% or more the initial body weight were associated with greater HbA1c reductions. CONCLUSION: This study supports oral semaglutide as an effective option for T2D treatment, offering improved glucose control and weight management in a real-world setting.

Short-term effectiveness of dapagliflozin versus DPP-4 inhibitors in elderly patients with type 2 diabetes: a multicentre retrospective study.

AIM: To compare effectiveness of dapagliflozin versus DPP-4 inhibitors on individualized HbA1c targets and extra-glycaemic endpoints among elderly patients with type 2 diabetes (T2D). METHODS: This was a multicentre retrospective study on patients aged 70-80 years with HbA1c above individualized target and starting dapagliflozin or DPP-4 inhibitors in 2015-2017. The primary outcome was the proportion reaching individualized HbA1c targets. Confounding by indication was addressed by inverse probability of treatment weighting (IPTW), multivariable adjustment (MVA), or propensity score matching (PSM). RESULTS: Patients initiating dapagliflozin (n = 445) differed from those initiating DPP-4i (n = 977) and balance between groups was achieved with IPTW or PSM. The median follow-up was 7.5 months and baseline HbA1c was 8.3%. A smaller proportion of patients initiating dapagliflozin attained individualized HbA1c target as compared to those initiating DPP-4 inhibitors (RR 0.73, p < 0.0001). IPTW, MVA, and PSM yielded similar results. Between-group difference in the primary outcome was observed among patients with lower eGFR or longer disease duration. Dapagliflozin allowed greater reductions in body weight and blood pressure than DPP-4 inhibitors. CONCLUSIONS: Elderly patients with T2D initiating dapagliflozin had a lower probability of achieving individualized HbA1c targets than those initiating DPP-4 inhibitors but displayed better improvements in extra-glycaemic endpoints.

Pre-operative micronutrient deficiencies in patients with severe obesity candidates for bariatric surgery.

PURPOSE: In patients with obesity, micronutrient deficiencies have been reported both before and after bariatric surgery (BS). Obesity is a chronic pro-inflammatory status, and inflammation increases the risk of micronutrient malnutrition. Our objective was to assess in pre-BS patients the prevalence of micronutrient deficiencies and their correlation with blood values of C-reactive protein (CRP). METHODS: Anthropometric data, instrumental examinations, and blood variables were centrally measured in the first 200 patients undergoing a pre-BS evaluation at the "Città della Salute e della Scienza" Hospital of Torino, starting from January 2018. RESULTS: At least one micronutrient deficiency was present in 85.5% of pre-BS patients. Vitamin D deficiency was the most prevalent (74.5%), followed by folate (33.5%), iron (32%), calcium (13%), vitamin B12 (10%), and albumin (5.5%) deficiency. CRP values were high (> 5 mg/L) in 65% of the patients. These individuals showed increased rate of iron, folate, vitamin B12 deficiency, and a higher number of micronutrient deficiencies. In a multiple logistic regression model, increased CRP levels were significantly associated with deficiencies of vitamin B12 (OR = 5.84; 95% CI 1.25-27.2; p = 0.024), folate (OR = 4.02; 1.87-8.66; p < 0.001), and with the presence of ≥ 2 micronutrient deficiencies (OR = 2.31; 1.21-4.42; p = 0.01). CONCLUSIONS: Micronutrient deficiencies are common in patients with severe obesity undergoing BS, especially when inflammation is present. In the presence of increased CRP values before surgery, it might be advisable to search for possible multiple micronutrient deficiencies.

Impaired taste sensation in type 2 diabetic patients without chronic complications: a case-control study.

PURPOSE: Few and contradictory data suggest changes in taste perception in type 2 diabetes (T2DM), potentially altering food choices. We, therefore, analyzed taste recognition thresholds in T2DM patients with good metabolic control and free of conditions potentially impacting on taste, compared with age-, body mass index-, and sex-matched normoglycemic controls. METHODS: An ascending-concentration method was used, employing sucrose (sweet), sodium chloride (salty), citric acid (sour), and quinine hydrochloride (bitter), diluted in increasing concentration solutions. The recognition threshold was the lowest concentration of correct taste identification. RESULTS: The recognition thresholds for the four tastes were higher in T2DM patients. In a multiple regression model, T2DM [ß = 0.95; 95% CI 0.32-1.58; p = 0.004 (salty); ß = 0.61; 0.19-1.03; p = 0.006 (sweet); ß = 0.78; 0.15-1.40; p = 0.016 (sour); ß = 0.74; 0.22-1.25; p = 0.006 (bitter)] and waist circumference [ß = 0.05; 0.01-0.08; p = 0.012 (salty); ß = 0.03; 0.01-0.05; p = 0.020 (sweet); ß = 0.04; 0.01-0.08; p = 0.020 (sour); ß = 0.04; 0.01-0.07; p = 0.007 (bitter)] were associated with the recognition thresholds. Age was associated with salty (ß = 0.06; 0.01-0.12; p = 0.027) and BMI with sweet thresholds (ß = 0.06; 0.01-0.11; p = 0.019). CONCLUSIONS: Taste recognition thresholds were higher in uncomplicated T2DM, and central obesity was significantly associated with this impairment. Hypogeusia may be an early sign of diabetic neuropathy and be implicated in the poor compliance of these patients to dietary recommendations.

Self-reported adherence to diet and preferences towards type of meal plan in patient with type 2 diabetes mellitus. A cross-sectional study.

BACKGROUND AND AIMS: Few studies have evaluated the attitudes of patients with type 2 diabetes mellitus (T2DM) towards the given dietary plans. In this study, we aimed to evaluate: i) the self-reported adherence of T2DM patients to the prescribed diets; ii) the use of other types of diet schemes; iii) the patients' preferences towards the type of meal plans. METHODS AND RESULTS: A 16 multiple-choice items questionnaire was administered to 500 T2DM patients; 71.2% (356/500) of them had the perception of having received a dietary plan; only 163/356 declared to be fully adherent. The latter had lower BMI (25.8 ± 4.5 vs 29.1 ± 4.5 kg/m2, p < 0.001) than patients who were partly adherent. Among patients not following the given diet, 61.8% was eating in accordance to a self-made diet and 20.9% did not follow any diet. Only a few patients (2.4%) had tried a popular diet/commercial program. Most patients preferred either a "sufficiently free" (201/500) or a "free" (218/500) scheme. The use of supplements attracted younger, obese individuals, with higher education, and most managers. In a multinomial regression model, age and diabetes duration were inversely associated with the choice of a "rigid" scheme, diabetes duration and glycated hemoglobin levels were inversely correlated with a "free" diet choice, obesity was associated with a "strategic" scheme choice, while lower education (inversely) and obesity (directly) correlated with the preference for "supplement use". CONCLUSIONS: Socio-cultural/individual factors could affect attitudes and preferences of T2DM patients towards diet. These factors should be considered in order to draw an individually tailored dietary plan.

Is the timing of caloric intake associated with variation in diet-induced thermogenesis and in the metabolic pattern? A randomized cross-over study.

BACKGROUND/OBJECTIVES: Food-induced thermogenesis is generally reported to be higher in the morning, although contrasting results exist because of differences in experimental settings related to the preceding fasting, exercise, sleeping and dieting. To definitively answer to this issue, we compared the calorimetric and metabolic responses to identical meals consumed at 0800 hours and at 2000 hours by healthy volunteers, after standardized diet, physical activity, duration of fast and resting. SUBJECTS/METHODS: Twenty subjects (age range 20-35 years, body mass index=19-26 kg m(-)(2)) were enrolled to a randomized cross-over trial. They randomly received the same standard meal in the morning and, 7 days after, in the evening, or vice versa. A 30-min basal calorimetry was performed; a further 60-min calorimetry was done 120-min after the beginning of the meal. Blood samples were drawn every 30-min for 180-min. General linear models, adjusted for period and carry-over, were used to evaluate the 'morning effect', that is, the difference of morning delta (after-meal minus fasting values) minus evening delta (after-meal minus fasting values) of the variables. RESULTS: Fasting resting metabolic rate (RMR) did not change from morning to evening; after-meal RMR values were significantly higher after the morning meal (1916; 95% confidence interval (CI)=1792, 2041 vs 1756; 1648, 1863 kcal; P<0.001). RMR was significantly increased after the morning meal (90.5; 95% CI=40.4, 140.6 kcal; P<0.001), whereas differences in areas-under-the-curve for glucose (-1800; -2564,-1036 mg dl(-1) × h, P<0.001), log-insulin (-0.19; -0.30,-0.07 µU ml(-1) × h; P=0.001) and fatty free acid concentrations (-16.1;-30.0,-2.09 mmol l(-1) × h; P=0.024) were significantly lower. Delayed and larger increases in glucose and insulin concentrations were found after the evening meals. CONCLUSIONS: The same meal consumed in the evening determined a lower RMR, and increased glycemic/insulinemic responses, suggesting circadian variations in the energy expenditure and metabolic pattern of healthy individuals. The timing of meals should probably be considered when nutritional recommendations are given.

Ghrelin.

BACKGROUND: The gastrointestinal peptide hormone ghrelin was discovered in 1999 as the endogenous ligand of the growth hormone secretagogue receptor. Increasing evidence supports more complicated and nuanced roles for the hormone, which go beyond the regulation of systemic energy metabolism. SCOPE OF REVIEW: In this review, we discuss the diverse biological functions of ghrelin, the regulation of its secretion, and address questions that still remain 15 years after its discovery. MAJOR CONCLUSIONS: In recent years, ghrelin has been found to have a plethora of central and peripheral actions in distinct areas including learning and memory, gut motility and gastric acid secretion, sleep/wake rhythm, reward seeking behavior, taste sensation and glucose metabolism.

Acute effects of acylated ghrelin on salbutamol-induced metabolic actions in humans.

The aim of this study is to describe a potential modulatory effect of acute acylated ghrelin (AG) administration on the glucose, insulin, and free fatty acids (FFA) responses to salbutamol (SALBU). Six healthy young male volunteers underwent the following four testing sessions in random order at least 7 days apart: (a) acute AG administration (1.0 µg/kg i.v. as bolus at 0'); (b) SALBU infusion (0.06 µg/kg/min i.v. from -15' to +45'); (c) SALBU infusion+AG; and (d) isotonic saline infusion. Blood samples for glucose, insulin, and FFA levels were collected every 15 min. As expected, with respect to saline, SALBU infusion induced a remarkable increase in glucose (10.8±5.6 mmol/l×min; P<0.05), insulin (2436.8±556.9 pmol/l×min; P<0.05), and FFA (18.9±4.5 mmol/l×min; P<0.01) levels. A significant increase in glucose (7.4±3.9 mmol/l×min; P<0.05) and FFA levels (10.0±2.8 mmol/l×min; P<0.01) without significant variations in insulin levels were recorded after AG administration. Interestingly, the hyperglycemic effect of AG appeared to be significantly potentiated during SALBU infusion (26.7±4.8 mmol/l×min; P<0.05). On the other hand, the stimulatory effect of SALBU on insulin and FFA was not significantly modified by AG administration. The results of this study show that acute AG administration has a synergic effect with ß2-adrenergic receptor activation by SALBU on blood glucose increase, suggesting that their pharmacological hyperglycemic action takes place via different mechanisms. On the other hand, AG has a negligible influence on the other pharmacological metabolic effects of SALBU infusion.

Impact of short-term treatment with benzodiazepines and imidazopyridines on glucose metabolism in healthy subjects.

AIM: In the last years there has been a progressive reduction of the average duration of sleep and an increase in the incidence of sleep disturbances. At the same time, an increase of the incidence of the metabolic syndrome has been described, partly attributable to the progressive worsening of dietary habits and the increase in sedentary lifestyle. Recent studies suggest that adequate sleep is essential to maintain good glucose metabolism and sleep disturbances may contribute to the manifestation of the metabolic syndrome. Benzodiazepines (BZ), such as brotizolam, and imidazopyridines, such as zolpidem, are frequently used as hypnotics but their potential impact on glucose metabolism has never been evaluated so far. METHODS: In 12 healthy volunteers [age (mean ± SEM) 38.3 ± 8.1 years; body mass index (BMI) 21.9 ± 0.8 kg/m²] we studied glucose and insulin responses to oral glucose tolerance test (OGTT, 75 g) before and after 15 days treatment with brotizolam 0.25 mg/day or zolpidem 10 mg/day. RESULTS: Brotizolam increased glucose delta area under curve response to the OGTT by 122 % (p < 0.01) and zolpidem by 86 % (p < 0.01) without significant variations of insulin levels, suggesting an impact on insulin sensitivity and/or insulin secretion. CONCLUSIONS: This study suggests that BZ and imidazopyridines have a rapid glucometabolic effect that is detectable as early as after 15 days treatment.

The GH-releasing effect of acylated ghrelin in normal subjects is refractory to GH acute auto-feedback but is inhibited after short-term GH administration inducing IGF1 increase.

OBJECTIVE: GH secretion is regulated by an interplay between GH-releasing hormone (GHRH), somatostatin (SST), and other central and peripheral signals. Acylated ghrelin (AG) amplifies GH pulsatility acting, at least partially, independently from GHRH and SST. The GH response to GHRH is inhibited by recombinant human GH (rhGH), likely due to a SST-mediated negative GH auto-feedback. The effect of exogenous rhGH on the GH-releasing effect of AG has never been tested. DESIGN AND METHODS: In six healthy volunteers, we studied the GH response to acute AG administration (1.0 µg/kg i.v.) during saline or rhGH infusion (4.0 µg/kg per h i.v.) or after 4-day rhGH (10.0 µg/kg s.c.) administration. RESULTS: Compared with saline, rhGH infusion increased GH levels (P<0.01). During saline, acute i.v. AG induced a marked increase (P<0.01) in GH levels similar to those observed after AG administration during rhGH infusion. During s.c. rhGH, IGF1 levels rose from day 0 to day 5 (P<0.01). After 4-day s.c. rhGH, i.v. AG increased (P<0.01) GH levels, though significantly (P<0.05) less than on day 0. CONCLUSIONS: The marked somatotroph-releasing effect of AG is refractory to a direct GH auto-feedback whereas is markedly inhibited after 4-day rhGH administration, suggesting the possibility of a selective IGF1-mediated inhibitory feedback.

Metabolic effects of overnight continuous infusion of unacylated ghrelin in humans.

OBJECTIVE: To clarify the metabolic effects of an overnight i.v. infusion of unacylated ghrelin (UAG) in humans. UAG exerts relevant metabolic actions, likely mediated by a still unknown ghrelin receptor subtype, including effects on ß-cell viability and function, insulin secretion and sensitivity, and glucose and lipid metabolism. DESIGN: We studied the effects of a 16-h infusion (from 2100 to 1300  h) of UAG (1.0  µg/kg per h) or saline in eight normal subjects (age (mean±s.e.m.), 29.6±2.4 years; body mass index (BMI), 22.4±1.7  kg/m(2)), who were served, at 2100 and 0800  h respectively, with isocaloric balanced dinner and breakfast. Glucose, insulin, and free fatty acid (FFA) levels were measured every 20  min. RESULTS: In comparison with saline, UAG induced significant (P<0.05) changes in glucose, insulin, and FFA profiles. UAG infusion decreased glucose area under the curve (AUC) values by 10% (UAG(0 - 960  min): 79.0±1.7×10(3)  mg/dl per min vs saline(0- 960  min): 87.5±3.8×10(3)  mg/dl per min) and the AUC at night by 14% (UAG(180)(-)(660  min): 28.4±0.5×10(3)  mg/dl per min vs saline(180 - 660  min): 33.2±1.1×10(3)  mg/dl per min). The overall insulin AUC was not significantly modified by UAG infusion; however, insulin AUC observed after meals was significantly increased under the exposure to UAG with respect to saline at either dinner or breakfast. The FFA AUC values were decreased by 52% under the exposure to UAG in comparison with saline (UAG(0 - 960  min): 0.3±0.02×10(3)  mEq/l per min vs saline(0 - 960  min): 0.6±0.05×10(3)  mEq/l per min). CONCLUSIONS: Exposure to the i.v. administration of UAG improves glucose metabolism and inhibits lipolysis in healthy volunteers. Thus, in contrast to the diabetogenic action of AG, UAG displays hypoglycemic properties.

The metabolic response to the activation of the beta-adrenergic receptor by salbutamol is amplified by acylated ghrelin.

BACKGROUND: It is well recognized that beta-adrenergic receptors mediate important endocrine and metabolic actions. In fact, beta-adrenergic receptor activation negatively influences GH secretion while exerting relevant metabolic actions such as the stimulation of insulin secretion, glycogenolysis, and lipolysis. AIM: We have already shown that the activation of the GH secretagogue receptor (GHS-R)-1a by acylated ghrelin (AG) counteracts the inhibitory effect of salbutamol (SALB), a beta2-adrenergic agonist, on GH release. The aim of the present study in humans was to clarify whether the metabolic response to SALB is affected by the infusion of AG, also known to exert significant metabolic actions. METHODS: Six healthy young male volunteers underwent the following testing sessions in random order at least 5 days apart: a) SALB (0.06 microg/kg/min iv from 0 to 60 min) alone; b) SALB in combination with AG (1.0 microg/kg/min iv from -60 to 60 min); c) isotonic saline. Insulin, glucose, and free fatty acids (FFA) levels were evaluated every 15 min. RESULTS: As expected, with respect to saline, SALB administration tended to increase both insulin secretion [Delta area under the curve (DeltaAUC): 0.16+/-0.09 vs 0.003+/-0.077 x 10(3) microU/ml/min; p>0.05] and FFA levels (DeltaAUC: 8.0+/-7.3 vs -4.0+/-4.0 mEq/l/min; p>0.05), while glucose levels did not change. The metabolic response to SALB was significantly modified under the exposure of AG. In fact, under AG infusion, SALB elicited a more marked increase of FFA (DeltaAUC: 22.3+/-3.2 vs 8.0+/-7.3 mEq/l/min; p<0.05) as well as a slight elevation in insulin (DeltaAUC: 0.37+/-0.11 vs 0.16+/-0.09 x 10(3) microU/ml/min; p>0.05). Under AG, the baseline glucose levels were more elevated but, again, in combination with AG, SALB did not significantly modify glucose levels. CONCLUSIONS: Beta-adrenergic receptors and AG are likely to interact at the metabolic level. In humans, the lypolitic response to a beta2-adrenergic agonist such as SALB is amplified by AG. Meanwhile, during the co-treatment, the marginal insulinotropic effect was not associated with an increase in glycemia.

Circulating obestatin levels in normal and Type 2 diabetic subjects.

BACKGROUND: Obestatin has been discovered as a new product of the ghrelin gene. Its physiological actions are still a matter of debate, but it seems that this peptide is likely to be involved in the control of insulin secretion and action as well as of adipocyte function. It has been already shown that obestatin secretion in humans is negatively modulated by food intake. AIM: To clarify obestatin secretion in normal subjects and in patients with Type 2 diabetes (T2D) in basal conditions and after a standardized meal. SUBJECTS/METHODS: Five normal subjects and 5 T2D patients were studied during infusion of saline (iv for over 5 h from -120 to +180 min). A standardized lunch was served at 0 min. Obestatin, glucose, and insulin levels were assayed at -120, -90, -60, -45, -30, -15, 0, 15, 30, 45, 60, 90, 120, 150, and 180 min. RESULTS: From -120 to 0 min, obestatin levels in normal and T2D subjects were similar (area under the curve: 32.3+/-5.6 pg/ml/min vs 31.1+/-1.0 pg/ml/min). After the meal, circulating obestatin levels underwent a clear decrease in normal subjects (0 min: 300.6+/-34.7 pg/ml vs nadir at 60 min: 161.8+/-29.4 pg/ml; p=0.002) but not in diabetic patients (0 min: 267.2+/-16.5 pg/ml vs nadir at 180 min: 226.0+/-10.5 pg/ml). CONCLUSION: This study shows that normal and diabetic subjects display similar levels of circulating obestatin in fasting condition. However patients with T2D look refractory to the inhibitory effect of meal on obestatin secretion.

Secretin: Should we revisit its metabolic outcomes?

Metabolic pathologies such as Type 2 Diabetes have become a major health problem for worldwide populations. Unfortunately, efforts to cure and especially to prevent these significant global problems have so far been met with disappointment. Recently, the involvement of the gut-derived hormonal dysregulation in the development of obesity-related disturbances has been intensively studied. For instance, studies of gut-derived peptides such as peptide YY 3-36, glucagon-like peptide-1, oxyntomodulin and, more recently, ghrelin have significantly improved our understanding of mechanisms underlying weight and metabolic regulation. Even though early reports of the existence of secretin, the first peptide hormone to be described, date back as far as 1825, so much and yet so little is still known about its physiological role in mammals, including humans. However, recent years have provided a better understanding of how the release of secretin is regulated by enteral secretagogues. On the other hand, most basic questions about its role in the post-prandial regulation of metabolic functions in normal and pathophysiological conditions remain to be elucidated. The present work intends to review the physiology of secretin along with its central and peripheral outcomes on metabolic functions.

Plasma total and acylated Ghrelin concentrations in patients with clinical and subclinical thyroid dysfunction.

BACKGROUND: Results of circulating Ghrelin levels in hyper- or hypothyroidism are conflicting and only overt thyroid dysfunction has been evaluated. AIM: To evaluate in a large number of patients with thyroid disfunction whether: a) hyper- and hypothyroidism (clinical or subclinical) are associated with variations in both acylated (AG) and total Ghrelin (TG) concentrations, and b) correction of thyroid dysfunction is followed by variations in Ghrelin concentrations. SUBJECTS AND METHODS: Seventy-six hyperthyroids, 52 hypothyroids, 144 euthyroids with chronic autoimmune thyroiditis, and 109 euthyroid healthy controls were evaluated cross-sectionally and longitudinally. RESULTS: TG and AG were significantly lower in hyperthyroids than in controls or hypothyroids; the latter 2 groups did not differ. TG was significantly lower in overt than in subclinical hyperthyroids, with a trend to a reduction also in AG levels. No differences were found between subclinical hyperthyroids and controls. After thionamide treatment, TG and AG levels in hyperthyroids did not differ from controls. L-thyroxine management of hypothyroidism was not associated with significant Ghrelin variations. Plasma Ghrelin was independent of either thyroid or gastric autoimmunity. Plasma TG was negatively correlated with serum free thyroid hormone levels in hyperthyroids but not in hypothyroids. CONCLUSIONS: Plasma Ghrelin concentrations are reduced in overt but not in subclinical hyperthyroidism and normalize after restoration of euthyroidism. Hypothyroidism is not accompanied by significant changes in circulating Ghrelin.

Beta-adrenergic agonism does not impair the GH response to acylated ghrelin in humans.

BACKGROUND: Acylated ghrelin (AG) is a physiological GH secretion amplifier, in part stimulating GHRH neurones and antagonizing somatostatin activity. In humans, AG is one of the most potent pharmacological stimuli of GH secretion and, unlike GHRH, is refractory to the inhibitory effect of glucose, free fatty acids (FFA) and somatostatin. Somatotroph secretion is also profoundly modulated by the adrenergic system. Indeed, beta-adrenergic agonists abolish spontaneous and GHRH-stimulated GH secretion. Based on these data, the aim of the present study was to investigate the effects of beta adrenergic agonism on the GH response to AG. SUBJECTS AND MEASUREMENTS: Six young healthy male volunteers underwent: (a) acute AG intravenous (iv) administration (1.0 microg/kg); (b) salbutamol infusion (SLB; 0.06 microg/kg/min iv); (c) AG + SLB; and (d) saline infusion. In all sessions GH levels were assayed every 15 min from time -30 to +210 min. RESULTS: SLB induced a significant (P < 0.05) inhibition of spontaneous GH secretion that persisted up to 75 min after SLB withdrawal. AG induced a marked increase (P < 0.01) in GH that was not modified by SLB. CONCLUSIONS: The GH-releasing effect of AG is refractory to the inhibitory effect of SLB-induced beta-adrenergic receptor activation. Although further studies are needed to confirm these results during the lifespan and particularly during prolonged exposure to beta agonists, the present data clearly suggest that, among GH stimulatory tests, AG administration might be the most suitable in clinical conditions of chronic treatment with beta-2 agonists, such as in asthmatic disease.

The continuous infusion of acylated ghrelin enhances growth hormone secretion and worsens glucose metabolism in humans.

CONTEXT: Acylated ghrelin (AG) has been discovered as a natural ligand of the GH secretagogue receptor type 1a and is now recognized as an important orexigenic factor. Besides stimulation of GH secretion and appetite, it exerts other central and peripheral actions including modulation of insulin secretion, glucose and lipid metabolism. OBJECTIVE: To define the effects of the continuous iv infusion of AG in humans with particular attention to metabolic parameters. MATERIALS AND METHODS: We studied the effects of 16- h (from 21:00 to 13:00 h) infusion of AG (0.5 microg/kg/h) or saline in 8 young volunteers who were provided with isocaloric balanced meals. GH, cortisol, insulin, glucose, free fatty acid (FFA), and ghrelin levels were assayed every 20 min. RESULTS: AG infusion increased circulating total ghrelin to a steady state that was maintained over 16 h infusion of the peptide. With respect to saline, AG infusion significantly modified GH, cortisol, insulin, and glucose profiles and decreased FFA area under the curve (p<0.01). AG increased GH pulse frequency and approximate entropy (p<0.05). AG enhanced the glucose response to both dinner (p<0.02) and breakfast (p<0.03). AG infusion blunted the early insulin response to dinner (p<0.03) but enhanced the second-phase insulin response to dinner and breakfast (p<0.05). CONCLUSIONS: The continuous exposure to AG in humans enhances somatotroph secretion but also worsens glucose metabolism, although it inhibits lipolysis. These findings in normal young volunteers are consistent with data from studies in animals and suggest that acylated ghrelin is likely to play a negative role in glucose metabolism.

Sleep abnormalities in type 2 diabetes may be associated with glycemic control.

Sleep disturbances may be associated with impaired glucose metabolism. The aim of this study was to evaluate sleep duration and quality in relation to glycemic control in patients with type 2 diabetes. In a cross-sectional study, sleep duration and quality were assessed in 47 middle-aged patients with type 2 diabetes treated with oral agents and without sleep disturbing complications and 23 healthy control subjects similar by age, sex, body mass index, occupation and schooling. Sleep was recorded by wrist-actigraphy for three consecutive days under free-living conditions. Univariate analysis showed lower sleep maintenance (P = 0.002) and sleep efficiency (P = 0.005), and higher fragmentation index (P < 0.0001), total activity score (P = 0.05) and moving time (P < 0.0001) in patients with type 2 diabetes. After adjusting for age, gender and schooling, fragmentation index and moving time remained significantly higher in the patients with diabetes (P < 0.05, both). HbA1c correlated inversely with sleep efficiency (r = -0.29; P = 0.047) and positively with moving time (r = 0.31; P = 0.031). These findings suggest that type 2 diabetes is associated with sleep disruptions even in the absence of complications or obesity. The relevance of sleep abnormalities to metabolic control and possible strategies to improve sleep quality in type 2 diabetes deserve further investigation.

Primary hyperparathyroidism is associated with marked impairment of GH response to acylated ghrelin.

BACKGROUND: Impaired GH secretion is a common finding in patients with primary hyperparathyroidism (PHP). Ghrelin displays strong GH-releasing action, mainly at the hypothalamic level. OBJECTIVE: To evaluate secretory response of GH to ghrelin in PHP patients. PATIENTS: Fifteen patients [11 women/4 men, mean age 54 years, range 32-70 years, body mass index (BMI) 25.0 +/- 0.7 kg/m(2)] affected with PHP due to single parathyroid adenoma and 35 normal age-matched subjects (23 women/12 men, mean age 58 years, range 35-68 years, BMI 24.1 +/- 1.1 kg/m(2)). METHODS: A measure of 1 microg/kg body weight i.v. acylated ghrelin or 1 microg/kg body weight i.v. GH releasing hormone (GHRH) followed by 0.5 g/kg body weight i.v. arginine (ARG) hydrochloride were administered to all subjects on alternate days in order to evaluate GH response. RESULTS: Mean serum GH peak after GHRH + ARG was 32.6 +/- 7.8 and 17.4 +/- 4.0 microg/l, in controls and PHP patients, respectively (P < 0.05). Mean serum GH peak after ghrelin was 70.4 +/- 31.5 and 16.8 +/- 1.9 microg/l, in controls and PHP patients, respectively, (P < 0.001). Using ROC curves, a serum GH peak > 22 microg/l after ghrelin stimulation might be considered as a cut-off value for identifying normal subjects. Ten (67%) PHP patients have impaired GH response to GHRH + ARG and 13 (87%) to ghrelin. Serum GH peak after ghrelin or GHRH + ARG was unrelated to serum IGF-1, PTH or ionized calcium concentrations. CONCLUSIONS: The present data confirm that GH secretion is impaired in PHP patients using the potent GH secretagogue ghrelin and suggest that impaired GH secretion is likely due to a deleterious effect of hypercalcaemia at the hypothalamic level in PHP patients.