There is a rising worldwide prevalence of diabetes, especially type 2 diabetes mellitus (T2DM), which is one of the most challenging health problems in the 21st century. The associated complications of diabetes, such as cardiovascular disease, peripheral vascular disease, stroke, diabetic neuropathy, amputations, renal failure, and blindness result in increasing ...

G protein-coupled receptor 119 (GPR119) was originally identified as a β-cell receptor. However, GPR119 activation also promotes incretin secretion and enhances peptide YY action. We examined whether GPR119-dependent control of glucose homeostasis requires preservation of peptidergic pathways in vivo. Insulin secretion was assessed directly in islets, and glucoregulation was examined ...

Synthetic glucagon-like peptide-1 (7-36)amide (GLP-1) lowers postprandial (pp) glycemia by stimulating insulin and inhibiting glucagon release and delaying gastric emptying (GE). However, the biological effects of the endogenous peptide and their relative contributions to pp glycemia remain to be defined in detail. Using the specific GLP-1 receptor antagonist exendin(9-39)amide [Ex(9-39)], ...

Objective: Increased postprandial glucose-dependent insulinotropic polypeptide (GIP) and glucagon responses and reduced postprandial glucagon-like peptide-1 (GLP-1) responses have been observed in some patients with type 2 diabetes mellitus. The causality of these pathophysiological traits is unknown. We aimed to determine the impact of insulin resistance and reduced glucose tolerance on ...

Glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) are major incretins with important effects on glucoregulatory functions. The aim of this study was to investigate effects of GIP and GLP-1 on gastric emptying and appetite after a mixed meal, and effects on insulin secretion and glucose disposal in humans. Randomized ...

A stomach-preserving duodenal-jejunal bypass (DJB) has been used for the treatment of type 2 diabetes mellitus (DM) since Rubino et al. first reported a prospective trial. However, there has been no report on changes in incretin secretion after DJB. We aimed to investigate whether DJB changes incretin secretion in nonmorbidly ...

Type 2 diabetes mellitus causes significant morbidity and mortality on account of its progressive nature and results in considerable burden on healthcare resources. It is characterized by high circulating levels of glucose resulting from insulin resistance and impaired insulin secretion. Current treatment strategies have only limited long-term efficacy and tolerability ...

Infusion of carnitine has been observed to increase non-oxidative glucose disposal in several studies, but the effect of oral carnitine on glucose disposal in non-diabetic lean versus overweight/obese humans has not been examined. This study examined the effects of 14 days of L: -carnitine L: -tartrate oral supplementation (LC) on blood ...

The transcription factor 7-like 2 (TCF7L2) rs7903146 T allele associates with type 2 diabetes in several populations, possibly mediated via decreased incretin secretion and/or action and altered beta and alpha cell function. We aimed to study circulating levels of glucose, proinsulin, insulin, C-peptide, glucagon, glucagon-like peptide-1 (GLP-1), glucagon-like peptide-2 (GLP-2) ...

To review the differences between the human glucagon-like peptide-1 (GLP-1) molecule and the analogue liraglutide, and to summarise key data from the liraglutide preclinical study programme showing the therapeutic promise of this new agent. Liraglutide is a full agonist of the GLP-1 receptor and shares 97% of its amino acid ...

To review the non-glycaemic effects of liraglutide, including potential improvements in body weight, systolic blood pressure (SBP) and pancreatic beta-cell function. Liraglutide induced weight loss of around 2-3 kg compared with weight increases of 1-2 kg with active comparators such as insulin glargine, rosiglitazone and glimepiride. Exenatide demonstrated similar weight ...

Despite advances in the management of type 2 diabetes, glycaemic control remains suboptimal for many patients because of the complexities of disease progression and the need to balance improved glycaemic control against adverse treatment effects, particularly weight gain and hypoglycaemia. Thus, the development of new antidiabetes therapies continues in earnest. ...

The incretin hormones gastric inhibitory polypeptide and especially glucagon-like peptide (GLP) have an important physiological function in augmenting postprandial insulin secretion. Since GLP-1 may play a role in the pathophysiology and treatment of type 2 diabetes, assessment of meal-related GLP-1 secretory responses in type 2 diabetic patients vs healthy individuals ...

In the design of therapeutics to treat type 2 diabetes, researchers have exploited the observation that oral ingestion of nutrients leads to the secretion of glucose homeostasis-regulating incretin hormones (for example, glucagon-like-peptide-1) from the gut. Here, we discuss two recent papers that suggest that the "other" incretin hormone, gastric inhibitory ...

The contribution of small intestinal motor activity to nutrient absorption is poorly defined. A reduction in duodenal flow events after hyoscine butylbromide, despite no change in pressure waves, was associated with reduced secretion of the incretin hormones glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) and a delay in glucose ...

Glucagon-like peptide-1 (GLP-1) is an incretin hormone that decreases postprandial glycemic excursions by enhancing insulin secretion but with short half-life due to rapid inactivation by enzymatic N-terminal truncation. Therefore, efforts are being made to improve the stability of GLP-1 via modifying its structure or inhibiting dipeptidyl-peptidase IV (DPP IV), which ...

The multifactorial nature of the pathogenesis of T2DM provides an opportunity to combine treatments that act upon different mechanisms. In addition to improving insulin resistance and pancreatic β-cell dysfunction, the GLP-1 agonists and DPP-4 inhibitors improve the impaired incretin response, as well as increase insulin secretion and reduce glucagon secretion, ...

Glucose-dependent insulinotropic polypeptide (GIP) is an incretin hormone that potentiates nutrient-induced insulin release. To date, the physiological importance of GIP has received much less attention than its younger sister incretin hormone glucagon-like peptide-1. Thus, it is worthwhile to refocus on this important and somewhat neglected incretin hormone. The potential role ...

We evaluated incretin secretion and dipeptidyl peptidase (DPP)-IV activity in Korean type 2 diabetic patients compared with non-diabetic subjects. Type 2 diabetic patients showed intact GLP-1 and total GIP levels similar to those in non-diabetic subjects. Serum DPP-IV activity was significantly higher in type 2 diabetic patients (p=0.022).

Established therapies for type-2 diabetes effectively reduce blood glucose, but are often associated with adverse effects that pose risks to patient's health or diminish adherence to treatment. Weight gain, hypoglycaemia and gastrointestinal symptoms are commonly reported and some agents may not be safe for use in patients with renal impairment ...

Glucagon-like peptide (GLP)-1 receptor is encoded by GLP1R. The effect of genetic variation at this locus on the response to GLP-1 is unknown. This study assessed the effect of GLP1R polymorphisms on insulin secretion in response to hyperglycemia and to infused GLP-1 in nondiabetic subjects. Eighty-eight healthy individuals (aged 26.3 ...

Oxyntomodulin (Oxm) is a hormone which has been shown to exhibit a range of potentially beneficial actions for alleviation of obesity-diabetes. However, exploitation of Oxm-based therapies has been severely restricted due to degradation by the enzyme dipeptidylpeptidase-IV (DPP-IV). Thus, the aim of this study was to assess the glucose-lowering, insulin-releasing ...

Diabetes is characterized by insulin resistance and a reduction in insulin secretion, leading to progressive β-cell failure and loss of β-cell mass. Its central therapeutic issues are how to restore glucose responsiveness of β-cells to normal and counteract defects in insulin secretion. Native glucagon-like peptide-1 (GLP-1), which makes β-cells competent ...

Recent genome-wide association studies identified several novel risk genes for type 2 diabetes. The majority of these type 2 diabetes risk variants confer impaired pancreatic beta cell function. Though the molecular mechanisms by which common genetic variation within these loci affects beta cell function are not completely understood, risk variants ...

The pharmacology, pharmacokinetics, efficacy, safety, dosage and administration, adverse effects, and place in therapy of liraglutide, a glucagon-like peptide-1 (GLP-1) receptor agonist, are reviewed. Liraglutide, the first once-daily human GLP-1 analogue, retains 97% homology with the endogenous hormone and shares its glucose-dependent glucose-lowering action but has a considerably longer half-life ...

Type 2 diabetes mellitus (T2DM) is rapidly increasing in prevalence and is a major public health problem. It is a progressive disease which commonly requires multiple pharmacotherapy. Current options for treatment may have undesirable side effects (particularly weight gain and hypoglycaemia) and contraindications, and little effect on disease progression. Incretin ...

The aim of the study was to determine whether reactive hypoglycaemia in pancreas transplant recipients that followed administration of glucagon-like peptide-1 (GLP-1) was associated with excessive insulin, insufficient glucagon, or both. Methodology involved six portally drained pancreas recipients who received GLP-1 (1.5 pmol/kg/min) or placebo infusion on randomized occasions during ...

Glucagon-like peptide-1 (GLP-1) receptor agonists are a novel class of pharmacotherapy for type 2 diabetes. We investigated the effects of a novel, long-acting human GLP-1 analogue, taspoglutide, in the Zucker diabetic fatty (ZDF) rat, an animal model of type 2 diabetes. Blood glucose and plasma levels of insulin, peptide YY ...

In addition to the hypoglycemia and weight gain associated with many treatments for type 2 diabetes, alpha-glucosidase inhibitors, thiazolidinediones, metformin, sulfonylureas, and the glinides do not address all of the multiple defects existing in the pathophysiology of the disease. Cumulatively, these oral agents address the influx of glucose from the ...

The global obesity epidemic fuelled by our obesogenic environment, and the prevention and treatment of obesity are some of the most important health-care challenges of our time. Although influenced largely by genetic factors, body mass index (BMI) is also heavily dependent upon environmental (principally dietary) factors. Whilst bariatric surgery often ...

Ezetimibe is a potent inhibitor of cholesterol absorption by enterocytes. Although ezetimibe minimally affects the absorption of triglyceride, it is unknown whether ezetimibe affects the secretion of the incretin hormones glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1). It has been shown that ezetimibe-treated mice are protected from diet-induced insulin ...

Net glucose and SCFA flux and insulin secretion into the portal vein might be associated with the incretins glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1). Our objectives were to clarify this association and study the impact of 2 doses of dietary oat beta-glucan on the variables. Three 35-kg portal ...

Variants in transcription factor 7-like 2 (266096218TCF7L2266096218USuser266096218Gene names have been italicized per house style. Please check and confirm whether there are other instances that need to be italicized or instances where italics have been inappropriately applied.) gene have been found strongly associated with an increased risk of type 2 diabetes, ...

The hindgut hypothesis posits improvements in Type 2 diabetes after gastric bypass surgery are due to enhanced delivery of undigested nutrients to the ileum, which increase incretin production and insulin sensitivity. The present study investigates the effect of ileal interposition (IT), surgically relocating a segment of distal ileum to the ...

Recently, glucagon-like peptide 1 (GLP1) and glucose-dependent insulinotropic polypeptide (GIP) have received much attention regarding possible roles in aetiology and treatment of type 2 diabetes. However, peptides co-secreted from the same enteroendocrine cells are less well studied. The present investigation was designed to characterise the in vitro and in vivo ...

Type 2 diabetes mellitus (T2DM) has been shown to be characterised by an almost abolished incretin effect. The incretin effect refers to the phenomenon of oral glucose eliciting a higher insulin response than intravenous glucose at identical plasma glucose profiles. It is conveyed by the two insulinotropic incretin hormones: glucagon-like ...

Incretins are hormones that are released after ingestion of a meal and augment the secretion of insulin. Current research suggests that GLP-1 (glucagon-like peptide 1) is the most important. Their action is terminated by enzymes known as dipeptidyl peptidase-4 (DPP-4). The observation that the incretin response may be diminished in ...

Recent research into the mechanisms of type 2 diabetes reveals intricate interactions among many hormonal processes. Ultimately, these pathways lead to hyperglycemia, pancreatic beta-cell failure, and the emergence of type 2 diabetes. The incretin hormones, glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP), are now known to play major roles ...

MKC253 is glucagon-like peptide 1 (GLP-1, 7-36 amide) adsorbed onto Technosphere microparticles for oral inhalation. The pharmacokinetics of inhaled GLP-1 and the pharmacokinetic-pharmacodynamic (PK-PD) relationship between inhaled GLP-1 and insulin were analyzed in two trials, one in healthy normal volunteers and the other in patients with type 2 diabetes. Inhaled ...

Incretins are hormones released by enteroendocrine cells in response to meals, depending upon absorption of nutrients. The present study aimed to elucidate the mechanisms through which a high-fat diet (HFD) induces insulin resistance and insulin hypersecretion by focusing on the effects on enteroendocrine cells, especially those secreting glucose-dependent insulinotropic polypeptide ...

Dipeptidyl peptidase IV (DPP-IV) inhibiton is a well recognized approach to treat Type 2 diabetes. RBx-0597 is a novel DPP-IV inhibitor discovered in our laboratory. The aim of the present study was to characterize the pharmacological profiles of RBx-0597 in vitro and in vivo as an anti-diabetic agent. RBx-0597 inhibited ...

Glucagon-like peptide-1 (GLP-1) improves insulin sensitivity in humans and rodents. It is currently unknown to what extent the (metabolic) effects of GLP-1 treatment are mediated by central GLP-1 receptors. We studied the impact of central GLP-1 receptor (GLP-1R) antagonism on the metabolic effects of peripheral GLP-1 administration in mice. High-fat-fed ...

OBJECTIVE: To evaluate the efficacy and tolerability of combination glucagon-like peptide-1 (GLP-1) analogs and insulin in the management of type 2 diabetes mellitus (T2DM) in adults. DATA SOURCE: A MEDLINE search (1966-April 2010) was conducted using the key terms glucagon-like peptide-1 analog, exenatide, incretin mimetic, liraglutide, diabetes mellitus, and insulin. ...

The glucagon-like peptide-1 (GLP-1) receptor represents an established therapeutic target in type 2 diabetes mellitus (T2DM). Agents that activate this receptor improve glucose tolerance alongside a low risk of hypoglycaemia, and have the potential to modify disease progression. Lixisenatide is a new potent and selective GLP-1 receptor agonist currently in ...

The reduced levels of glucagon-like peptide 1 (GLP-1) after an oral glucose load in Type 2 diabetic patients could be dependent either on a reduced synthesis or an increased degradation; but GLP-1 and dipeptidyl peptidase IV (DPP-IV) levels during an oral glucose tolerance test (OGTT) have not been studied together. ...

Post-prandial hyperglycemia, hyperlipidemia, and endothelial dysfunction play an important role in the pathogenesis of atherosclerosis. Improvement in post-prandial hyperglycemia on alpha-glucosidase inhibitors (alpha-GIs) is associated with a risk reduction of cardiovascular diseases, but the post-prandial effects of alpha-GIs on endothelial function and incretin secretion in type 2 diabetic patients with ...

Type 1 diabetes (T1D) in both humans and BioBreeding (BB) rats is an autoimmune disease that results in complete destruction of islets and insulin dependency for life. Glucagon-like peptide 1 (GLP-1) promotes beta cell proliferation and neogenesis and has a potent insulinotropic effect. We hypothesized that the expression of GLP-1 ...

The gastrointestinal hormones glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1), termed incretins, are essential regulators of normal glucose homeostasis. Research indicates that the incretin effect is impaired in type 2 diabetes, and this seems to be a consequence rather than a cause of type 2 diabetes. This review describes ...

Incretin-based therapies encompass two new classes of antidiabetic drugs: glucagon-like peptide-1 (GLP-1) receptor agonists (e.g., liraglutide, exenatide, and exenatide long-acting release), which are structurally related to GLP-1, and the dipeptidyl peptidase-4 (DPP-4) inhibitors (e.g., sitagliptin and saxagliptin), which limit the breakdown of endogenous GLP-1. To evaluate the safety and effectiveness ...

Analogues of the incretins Glucagon-like peptide 1 (GLP-1) and Glucose-dependent insulinotropic peptide (GIP) have been developed to treat type 2 diabetes mellitus. They are protease resistant and have a longer biological half life than the native peptides. Some of these novel analogues can cross the blood-brain barrier, have neuroprotective effects, ...