Gut-derived hormones, such as GLP-1, have been proposed to relay information to the brain to regulate appetite. GLP-1 receptor agonists, currently used for the treatment of type 2 diabetes (T2DM), ...improve glycemic control and stimulate satiety, leading to decreases in food intake and body weight. We hypothesized that food intake reduction after GLP-1 receptor activation is mediated through appetite- and reward-related brain areas. Obese T2DM patients and normoglycemic obese and lean individuals (n = 48) were studied in a randomized, crossover, placebo-controlled trial. Using functional MRI, we determined the acute effects of intravenous administration of the GLP-1 receptor agonist exenatide, with or without prior GLP-1 receptor blockade using exendin 9-39, on brain responses to food pictures during a somatostatin pancreatic-pituitary clamp. Obese T2DM patients and normoglycemic obese versus lean subjects showed increased brain responses to food pictures in appetite- and reward-related brain regions (insula and amygdala). Exenatide versus placebo decreased food intake and food-related brain responses in T2DM patients and obese subjects (in insula, amygdala, putamen, and orbitofrontal cortex). These effects were largely blocked by prior GLP-1 receptor blockade using exendin 9-39. Our findings provide novel insights into the mechanisms by which GLP-1 regulates food intake and how GLP-1 receptor agonists cause weight loss.
Summary Background Diabetes treatments are needed that are convenient, provide effective glycaemic control, and do not cause weight gain. We aimed to test the hypothesis that improvement in ...haemoglobin A1c (HbA1c ) achieved with once weekly exenatide was superior to that achieved with insulin glargine titrated to glucose targets. Methods In this 26-week, open-label, randomised, parallel study, we compared exenatide with insulin glargine in adults with type 2 diabetes who had suboptimum glycaemic control despite use of maximum tolerated doses of blood-glucose-lowering drugs for 3 months or longer. Patients were randomly assigned to add exenatide (2 mg, once-a-week injection) or insulin glargine (once-daily injection, starting dose 10 IU, target glucose range 4·0–5·5 mmol/L) to their blood-glucose-lowering regimens. Randomisation was with a one-to-one allocation and block size four, stratified according to country and concomitant treatment (70% metformin only; 30% metformin plus sulphonylurea). Participants and clinical investigators were not masked to assignment, but investigators analysing data were. The primary endpoint was change in HbA1c from baseline, and analysis of this outcome was by modified intention to treat for all patients who received at least one dose of study drug. This trial is registered at ClinicalTrials.gov , number NCT00641056. Findings 456 patients were randomly allocated to treatment and were included in the modified intention-to-treat analysis (233 exenatide, 223 insulin glargine). Participants who received at least one dose of study drug and for whom baseline and at least one postbaseline measurement of HbA1c were available were included in the primary efficacy analysis. Change in HbA1c at 26 weeks was greater in patients taking exenatide (n=228; −1·5%, SE 0·05) than in those taking insulin glargine (n=220; −1·3%, 0·06; treatment difference −0·16%, 0·07, 95% CI −0·29 to −0·03). 12 (5%) of 233 patients allocated to exenatide and two (1%) of 223 taking insulin glargine discontinued participation because of adverse events (p=0·012). A planned extension period (up to 2·5 years' duration) is in progress. Interpretation Once weekly exenatide is an important therapeutic option for patients for whom risk of hypoglycaemia, weight loss, and convenience are particular concerns. Funding Amylin Pharmaceuticals; Eli Lilly and Company.
Patients with type 1 diabetes who have impaired awareness of hypoglycaemia have a three to six times increased risk of severe hypoglycaemia. We aimed to assess whether continuous glucose monitoring ...(CGM) improves glycaemia and prevents severe hypoglycaemia compared with self-monitoring of blood glucose (SMBG) in this high-risk population.
We did a randomised, open-label, crossover trial (IN CONTROL) at two medical centres in the Netherlands. Eligible participants were patients diagnosed with type 1 diabetes according to American Diabetes Association criteria, aged 18-75 years, with impaired awareness of hypoglycaemia as confirmed by a Gold score of at least 4, and treated with either continuous subcutaneous insulin infusion or multiple daily insulin injections and doing at least three SMBG measurements per day. After screening, re-education about diabetes management, and a 6-week run-in phase (to obtain baseline CGM data), we randomly assigned patients (1:1) with a computer-generated allocation sequence (block size of four) to either 16 weeks of CGM followed by 12 weeks of washout and 16 weeks of SMBG, or 16 weeks of SMBG followed by 12 weeks of washout and 16 weeks of CGM (where the SMBG phase was the control). During the CGM phase, patients used a real-time CGM system consisting of a Paradigm Veo system with a MiniLink transmitter and an Enlite glucose sensor (Medtronic, CA, USA). During the SMBG phase, patients were equipped with a masked CGM device, consisting of an iPro 2 continuous glucose monitor and an Enlite glucose sensor, which does not display real-time glucose values. The number of SMBG measurements per day and SMBG systems were not standardised between patients, to mimic real-life conditions. During both intervention periods, patients attended follow-up visits at the centres each month and had telephone consultations 2 weeks after each visit inquiring about adverse events, episodes of hypoglycaemia, etc. The primary endpoint was the mean difference in percentage of time spent in normoglycaemia (4-10 mmol/L) over the total intervention periods, analysed on an intention-to-treat basis. Severe hypoglycaemia (requiring third party assistance) was a secondary endpoint. This trial is registered with ClinicalTrials.gov, number NCT01787903.
Between March 4, 2013, and Feb 9, 2015, we recruited and randomly assigned 52 patients to either the CGM-SMBG sequence (n=26) or the SMBG-CGM sequence (n=26). The last patient visit was on March 21, 2016. Time spent in normoglycaemia was higher during CGM than during SMBG: 65·0% (95% CI 62·8-67·3) versus 55·4% (53·1-57·7; mean difference 9·6%, 95% CI 8·0-11·2; p<0·0001), with reductions in both time spent in hypoglycaemia (ie, blood glucose ≤3·9 mmol/L 6·8% vs 11·4%, mean difference 4·7%, 3·4-5·9; p<0·0001) and time spent in hyperglycaemia (ie, blood glucose >10 mmol/L 28·2% vs 33·2%, mean difference 5·0%, 3·1-6·9; p<0·0001). During CGM, the number of severe hypoglycaemic events was lower (14 events vs 34 events, p=0·033). Five serious adverse events other than severe hypoglycaemia occurred during the trial, but all were deemed unrelated to the trial intervention. Additionally, no mild to moderate adverse events were related to the trial intervention.
CGM increased time spent in normoglycaemia and reduced severe hypoglycaemia in patients with type 1 diabetes and impaired awareness of hypoglycaemia, compared with SMBG. Our results support the concept of using CGM in this high-risk population.
Eli Lilly and Sanofi.
Diabetic nephropathy is the leading cause of end-stage renal disease worldwide, and is associated with a high risk of cardiovascular morbidity and mortality. Intensive control of glucose levels and ...blood pressure is currently the mainstay of both prevention and treatment of diabetic nephropathy. However, this strategy cannot fully prevent the development and progression of diabetic nephropathy, and an unmet need remains for additional novel therapies. The incretin-based agents--agonists of glucagon-like peptide 1 receptor (GLP-1R) and inhibitors of dipeptidyl peptidase 4 (DPP-4), an enzyme that degrades glucagon-like peptide 1--are novel blood-glucose-lowering drugs used in the treatment of type 2 diabetes mellitus (T2DM). Therapeutic agents from these two drug classes improve pancreatic islet function and induce extrapancreatic effects that ameliorate various phenotypic defects of T2DM that are beyond glucose control. Agonists of GLP-1R and inhibitors of DPP-4 reduce blood pressure, dyslipidaemia and inflammation, although only GLP-1R agonists decrease body weight. Both types of incretin-based agents inhibit renal tubular sodium reabsorption and decrease glomerular pressure as well as albuminuria in rodents and humans. In rodents, incretin-based therapies also prevent onset of the morphological abnormalities of diabetic nephropathy.
Objectives The purpose of this study was to compare myocardial triglyceride content and function between patients with uncomplicated type 2 diabetes mellitus (T2DM) and healthy subjects within the ...same range of age and body mass index (BMI), and to study the associations between myocardial triglyceride content and function. Background T2DM is a major risk factor for cardiovascular disease. Increasing evidence is emerging that lipid oversupply to cardiomyocytes plays a role in the development of diabetic cardiomyopathy, by causing lipotoxic injury and myocardial steatosis. Methods Myocardial triglyceride content and myocardial function were measured in 38 T2DM patients and 28 healthy volunteers in the same range of age and BMI by proton magnetic resonance (MR) spectroscopy and MR imaging, respectively. Myocardial triglyceride content was calculated as a percentage relative to the signal of myocardial water. Results Myocardial triglyceride content was significantly higher in T2DM patients compared with healthy volunteers (0.96 ± 0.07% vs. 0.65 ± 0.05%, p < 0.05). Systolic function did not significantly differ between both groups. Indexes of diastolic function, including the ratio of maximal left ventricular early peak filling rate and the maximal left ventricular atrial peak filling rate (E/A) and E peak deceleration, were significantly impaired in T2DM compared with those in healthy subjects (1.08 ± 0.04 ml/s2 × 10−3 vs. 1.24 ± 0.06 ml/s2 × 10−3 and 3.6 ± 0.2 ml/s2 × 10−3 vs. 4.4 ± 0.3 ml/s2 × 10−3 , respectively, p < 0.05). Multivariable analysis indicated that myocardial triglyceride content was associated with E/A and E peak deceleration, independently of diabetic state, age, BMI, heart rate, visceral fat, and diastolic blood pressure. Conclusions Myocardial triglyceride content is increased in uncomplicated T2DM and is associated with impaired left ventricular diastolic function, independently of age, BMI, heart rate, visceral fat, and diastolic blood pressure.
When patients with type 2 diabetes start their first injectable therapy, clinicians can choose between glucagon-like peptide-1 (GLP-1) receptor agonists and basal insulins. In DURATION-3, exenatide ...once weekly was compared with insulin glargine (henceforth, glargine) as first injectable therapy. Here, we report the results of the final 3-year follow-up.
DURATION-3 was an open-label randomised trial done between May 13, 2008, and Jan 30, 2012. Patients with type 2 diabetes aged 18 years or older were enrolled at 72 sites worldwide. They were eligible when they had suboptimum glycaemic control (HbA1c 7.1-11.0% 54-97 mmol/mol) despite maximum tolerated doses of metformin alone or with a sulfonylurea for at least 3 months, a stable bodyweight for at least 3 months, and a BMI of 25-45 kg/m(2) (23-45 kg/m(2) in South Korea and Taiwan). Patients were randomly assigned (1:1) by computer-generated random sequence with an interactive voice-response system (block size four, stratified by country and concomitant therapy) to once-weekly exenatide (2 mg subcutaneous injection) or once-daily glargine (titrated to target) to be given in addition to their existing oral glucose-lowering regimens. The primary efficacy measure at 3 years was change in HbA1c from baseline in patients given at least one dose of the assigned drug (ie, analyses by modified intention to treat). Patients, investigators, and data analysts were not masked to treatment assignment. This trial is registered with ClinicalTrials.gov, number NCT00641056.
456 patients underwent randomisation and received at least one dose of the assigned drug (233 given exenatide, 223 glargine). At 3 years, least-squares mean HbA1c change was -1.01% (SE 0.07) in the exenatide group versus -0.81% (0.07) in the glargine group (least-squares mean difference -0.20%, SE 0.10, 95% CI -0.39 to -0.02; p=0.03). Transient gastrointestinal adverse events characteristic of GLP-1 receptor agonists were more frequent with exenatide than glargine (nausea: 36 15% of 233 patients vs five 2% of 223; vomiting: 15 6% vs six 3%; diarrhoea: 32 14% vs 15 7%), although frequency of these events did decrease after week 26 in the exenatide group. The proportion of patients who reported serious adverse events in the exenatide group (36 patients 15%) was the same as that in the glargine group (33 15%). The exposure-adjusted rate of overall hypoglycaemia was three times higher in patients given glargine (0.9 events per patient per year) than in those given exenatide (0.3 events per patient per year).
Efficacy of once-weekly exenatide is sustained for 3 years. GLP-1 receptor agonists could be a viable long-term injectable treatment option in patients with type 2 diabetes who have not yet started taking insulin.
Amylin Pharmaceuticals and Eli Lilly.
Abstract Alanine aminotransferase (ALT) is a marker of non-alcoholic fatty liver disease (NAFLD) and predicts incident type 2 diabetes mellitus (DM2). Recently, ALT was shown to be also associated ...with endothelial dysfunction and carotid atherosclerosis. We studied the predictive value of ALT for all-cause mortality, incident cardiovascular disease (CVD) and coronary heart disease (CHD) events in a population-based cohort of Caucasian men and women aged 50–75 years, at baseline. The 10-year risk of all-cause mortality, fatal and non-fatal CVD and CHD events in relation to ALT was assessed in 1439 subjects participating in the Hoorn Study, using Cox survival analysis. Subjects with prevalent CVD/CHD and missing data were excluded. As compared with the first tertile, the age- and sex-adjusted hazard ratios (95% confidence intervals) for all-cause mortality, CVD events and CHD events were 1.30 (0.92–1.83), 1.40 (1.09–1.81) and 2.04 (1.35–3.10), respectively, for subjects in the upper tertile of ALT. After adjustment for components of the metabolic syndrome and traditional risk factors, the association of ALT and CHD events remained significant for subjects in the third relative to those in the first tertile, with a hazard ratio of 1.88 (1.21–2.92) and 1.75 (1.12–2.73), respectively. In conclusion, the predictive value of ALT for coronary events, seems independent of traditional risk factors and the features of the metabolic syndrome in a population-based cohort. Further studies should confirm these findings and elucidate the pathophysiological mechanisms.
OBJECTIVE:--Insulin resistance, associated with increased lipolysis, results in a high exposure of nonadipose tissue to lipids. Experimental data indicate that fatty infiltration of pancreatic islets ...may also contribute to β-cell dysfunction, but whether this occurs in humans in vivo is unknown. RESEARCH DESIGN AND METHODS--Using proton magnetic resonance spectroscopy and oral glucose tolerance tests, we studied the association of pancreatic lipid accumulation in vivo and various aspects of β-cell function in 12 insulin-naive type 2 diabetic and 24 age- and BMI-matched nondiabetic men. RESULTS:--Patients versus control subjects had higher A1C, fasting plasma glucose, and insulin and triglyceride levels and lower HDL cholesterol, but similar waist circumference. Median (interquartile range) pancreatic fat content in patients and control subjects was 20.4% (13.4-43.6) and 9.7% (7.0-20.2), respectively (P = 0.032). Pancreatic fat correlated negatively with β-cell function parameters, including the insulinogenic index adjusted for insulin resistance, early glucose-stimulated insulin secretion, β-cell glucose sensitivity, and rate sensitivity (all P < 0.05), but not potentiation. However, these associations were significantly affected by the diabetic state, such that a significant association of pancreatic fat with β-cell dysfunction was only present in the nondiabetic group (all P < 0.01), suggesting that once diabetes occurs, factors additional to pancreatic fat account for further β-cell function decline. In control subjects, the association of pancreatic fat and β-cell function remained significant after correction for BMI, fasting plasma glucose, and triglycerides (P = 0.006). CONCLUSIONS:--These findings indicate that pancreatic lipid content may contribute to β-cell dysfunction and possibly to the subsequent development of type 2 diabetes in susceptible humans.
Objectives The purpose of this study was to investigate the relationship between hepatic triglyceride content and both myocardial function and metabolism in type 2 diabetes mellitus (T2DM). ...Background Heart disease is the leading cause of mortality in T2DM. Central obesity and hepatic steatosis, both hallmark abnormalities in T2DM, have been related to increased risk of heart disease. Methods Sixty-one T2DM patients underwent myocardial perfusion and substrate metabolism measurements by positron emission tomography, using 15 Owater, 11 Cpalmitate, and 18 F-2-fluoro-2-deoxy- d -glucose. In addition, whole-body insulin sensitivity (M/I) was determined. Myocardial left ventricular function and high-energy phosphate metabolism were measured using magnetic resonance imaging and 31 P-magnetic resonance spectroscopy, respectively. Hepatic triglyceride content was measured by proton magnetic resonance spectroscopy. Patients were divided according to hepatic triglyceride content (T2DM-low ≤5.56% vs. T2DM-high >5.56%). Results In addition to decreased M/I (p = 0.002), T2DM-high patients had reduced myocardial perfusion (p = 0.001), glucose uptake (p = 0.005), and phosphocreatine/adenosine triphosphate (PCr/ATP) ratio (p = 0.003), compared with T2DM-low patients, whereas cardiac fatty acid metabolism and left ventricular function were not different. Hepatic triglyceride content correlated inversely with M/I (Pearson's r = −0.620, p < 0.001), myocardial glucose uptake (r = −0.413, p = 0.001), and PCr/ATP (r = −0.442, p = 0.027). Insulin sensitivity correlated positively with myocardial glucose uptake (r = 0.528, p < 0.001) and borderline with myocardial PCr/ATP (r = 0.367, p = 0.072), whereas a positive association was found between cardiac glucose uptake and PCr/ATP (r = 0.481, p = 0.015). Conclusions High liver triglyceride content in T2DM was associated with decreased myocardial perfusion, glucose uptake, and high-energy phosphate metabolism in conjunction with impaired M/I. The long-term clinical implications of hepatic steatosis with respect to cardiac metabolism and function in the course of T2DM require further study.
To study the effect of exenatide on body composition and circulating cardiovascular risk biomarkers.
Metformin-treated patients with type 2 diabetes (N = 69) were randomized to exenatide or insulin ...glargine and treated for 1 year. Body composition was evaluated by dual-energy X-ray absorptiometry. Additionally, body weight, waist circumference, and cardiovascular biomarkers were measured.
Treatment with exenatide for 1 year significantly reduced body weight, waist circumference, and total body and trunkal fat mass by 6, 5, 11, and 13%, respectively. In addition, exenatide increased total adiponectin by 12% and reduced high-sensitivity C-reactive protein by 61%. Insulin glargine significantly reduced endothelin-1 by 7%. These changes were statistically independent of the change in total body fat mass and body weight.
Exenatide treatment for 1 year reduced body fat mass and improved the profile of circulating biomarkers of cardiovascular risk. No significant changes were seen with insulin glargine except a trend for reduced endothelin-1 levels.
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