Postprandial Glucose-dependent Insulinotropic Polypeptide Levels Research Articles

Impact of dipeptidyl peptidase-4 inhibitors on glucose-dependent insulinotropic polypeptide in type 2 diabetes mellitus: a systematic review and meta-analysis.

Glucose-dependent insulinotropic polypeptide (GIP) confers a variety of metabolic benefits in type 2 diabetes mellitus (T2DM). This meta-analysis was conducted to investigate the impact of dipeptidyl peptidase 4 (DPP4) inhibitors on GIP levels in T2DM patients. Medline (PubMed), CENTER (Cochrane Library), and Embase (Ovid) were searched and randomized controlled trials (RCTs) evaluating the impact of DPP4 inhibitors on fasting and postprandial GIP levels were obtained. For postprandial GIP, only studies with the data of GIP changes reported as the total area under the curve (AUCGIP) using a meal or oral glucose tolerance test were included. A random-effects model was used for data pooling after incorporating heterogeneity. Overall, 14 RCTs with 541 T2DM patients were included. Compared to placebo/no treatment, the use of DPP4 inhibitors significantly increased the fasting GIP level (standard mean difference [SMD]: 0.77, 95% confidence interval [CI]: 0.48-1.05, P<0.001; I2=52%) and postprandial AUCGIP (SMD: 1.33, 95% CI: 1.02-1.64, P<0.001; I2=65%). Influence analysis by excluding one dataset at a time showed consistent results. Sensitivity analyses only including studies with radioimmunoassay showed also consistent results (fasting GIP: SMD: 0.75, 95% CI: 0.51-1.00, P<0.001; I2=0%; and postprandial AUCGIP: SMD: 1.48, 95% CI: 1.18-1.78, P<0.001; I2=54%). Further subgroup analyses demonstrated that the influence of DPP4 inhibitors on fasting and postprandial GIP levels in T2DM patients was not significantly changed by study characteristics such as study design, patient mean age, baseline glycated hemoglobin (HbA1c) concentration, body mass index (BMI), background treatment, treatment duration, or method for postprandial GIP measurement (all P for subgroup effects <0.05). The use of DPP4 inhibitors effectively increases the fasting and postprandial GIP concentrations in T2DM patients. https://www.crd.york.ac.uk/prospero/, identifier CRD42022356716.

Canagliflozin Increases Postprandial Total Glucagon-Like Peptide1 Levels in the Absence of α-Glucosidase Inhibitor Therapy in Patients with Type 2 Diabetes: A Single-Arm, Non-randomized, Open-Label Study.

IntroductionTo investigate canagliflozin-induced changes in postprandial total glucagon-like peptide 1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) levels in patients with type 2 diabetes mellitus (T2DM).MethodsForty-five patients with T2DM who had inadequate glycemic control (glycated hemoglobin ≥ 6.5%) with diet and exercise alone (n = 15, drug naïve) and in combination with either a stable dose of the α-glucosidase inhibitor acarbose (n = 15) or metformin (n = 15) received canagliflozin, a sodium-glucose cotransporter 2 inhibitor, at 100 mg once daily for 12 weeks. The primary endpoint was the change from baseline to week 12 in postprandial glucose and plasma levels of total GLP-1 and GIP during a meal tolerance test (MTT).ResultsCanagliflozin significantly reduced postprandial blood glucose (mean difference − 40.2 mg/mL at 60 min) and increased postprandial total GLP-1 (mean difference 1.8 pg/mL at 60 min) during an MTT. A transient reduction in the postprandial GIP level at only 30 min (mean difference − 80.3 pg/mL) during an MTT was observed. No changes in postprandial GLP-1 or GIP levels were seen after canagliflozin treatment as an add-on to acarbose in patients with T2DM. Acarbose treatment significantly decreased postprandial total GIP levels (P < 0.05) and tended to increase postprandial total GLP-1 levels (P = 0.07) compared to the other two treatments prior to canagliflozin.ConclusionCanagliflozin 100 mg increased postprandial total GLP-1 levels in the absence of acarbose, suggesting that it may upregulate GLP-1 secretion through delayed glucose absorption in the upper intestine, as with the α-glucosidase inhibitor.Trial RegistrationUniversity Hospital Medical Information Network, UMIN000018345.FundingMitsubishi Tanabe Pharma Corporation.Electronic supplementary materialThe online version of this article (10.1007/s13300-019-00689-w) contains supplementary material, which is available to authorized users.

Postprandial levels of GLP-1, GIP and glucagon after 2 years of weight loss with a Paleolithic diet: a randomised controlled trial in healthy obese women.

ObjectiveTo investigate how weight loss by different diets impacts postprandial levels of glucagon-like peptide 1 (GLP-1), glucose-dependent insulinotropic polypeptide (GIP) and glucagon.MethodsIn this single-centre, parallel group 2-year trial, 70 healthy postmenopausal obese women were randomised to the Paleolithic diet or a healthy control diet based on Nordic Nutrition Recommendations. Both diets were without calorie restriction. The primary outcome was the change in fat mass. Here, secondary analyses on GLP-1, GIP and glucagon measured during an OGTT are described.ResultsIn the Paleolithic diet group, mean weight loss compared to baseline was 11% at 6 months and 10% at 24 months. In the control diet group, mean weight loss was 6% after 6 and 24 months (P = 0.0001 and P = 0.049 for the comparison between groups at 6 and 24 months respectively). Compared to baseline, the mean incremental area under the curve (iAUC) for GLP-1 increased by 34 and 45% after 6 and 24 months in the Paleolithic diet group and increased by 59% after 24 months in the control diet group. The mean iAUC for GIP increased only in the Paleolithic diet group. The area under the curve (AUC) for glucagon increased during the first 6 months in both groups. The fasting glucagon increase correlated with the β-hydroxybutyrate increase.ConclusionsWeight loss caused an increase in postprandial GLP-1 levels and a further rise occurred during weight maintenance. Postprandial GIP levels increased only after the Paleolithic diet. Reduced postprandial glucagon suppression may be caused by a catabolic state.

Severe hypoglycemia in a patient with anorexia nervosa

Severe hypoglycemia is an important but uncommon complication of anorexia nervosa. A 35-year-old woman showed severe hypoglycemia after a recovery from severe liver dysfunction due to malnutrition. To reveal the cause of severe hypoglycemia, we measured plasma hormones and performed a 75g oral glucose loading test. Fasting serum adrenocorticotropic hormone, cortisol, growth hormone, somatostatin, and active ghrelin were elevated. Serum free triiodothyronine, leptin, and adiponectin were reduced. Plasma glucose fluctuated from 67 to 76 mg/dl after a 75g glucose ingestion, without hyperinsulinemia. Serum growth hormone, somatostatin, and active ghrelin levels were decreased after glucose ingestion. Plasma glucagon levels were increased and remained at high levels at 120 min, and glucose-dependent insulinotropic polypeptide (GIP) levels were continuously and remarkably increased after glucose ingestion. We observed a strongly reduced sensitivity in glucagon-induced hepatic glycogenolysis, and significantly elevated fasting and postprandial GIP levels, and a defective GIP-mediated glucagon secretion, in an anorectic patient with severe hypoglycemia.

Increased glucose-dependent insulinotropic polypeptide (GIP) secretion in acromegaly.

Acromegaly is often associated with fasting and postprandial hyperinsulinemia, and the mechanisms involved are only partly understood. Hypersecretion of incretins such as glucose-dependent insulinotropic polypeptide (GIP) could play a role in determining hyperinsulinemia in acromegaly, but the available data are inconsistent. The aim of this study was to characterize the fasting and postprandial pattern of plasma GIP and insulin in a group of acromegalic patients. Eleven non-diabetic patients with newly diagnosed acromegaly and 11 sex- and age-matched healthy subjects were studied. Blood samples were taken at regular intervals in fasting conditions and for 3 h after a standard solid-liquid meal for growth hormone (GH), GIP and insulin measurements. Not only insulin, but also fasting and postprandial GIP levels were significantly higher in the patients with acromegaly than the healthy subjects (P<0.01). In the former group fasting GIP levels and the integrated GIP response to the meal correlated significantly with GH basal levels (r=0.83, P<0.01 and r=0.65, P<0.05, respectively). Moreover, multivariate linear regression analysis showed that the presence of acromegalic status was associated with higher fasting and postprandial GIP levels independently of sex, age, fasting and postprandial plasma glucose and insulin levels, and the occurrence of normal or impaired glucose tolerance. This study provides evidence that in patients with acromegaly fasting and postprandial GIP levels are abnormally high. GIP hypersecretion in turn might play a role in the pathogenesis of hyperinsulinemia that characterizes acromegaly.