Efficacy and tolerability of glucagon-like peptide-1 receptor agonists in patients with type 2 diabetes mellitus

Amylin receptor agonism enhances the effects of liraglutide in protecting against the acute metabolic side effects of olanzapine

Olanzapine is a second-generation antipsychotic (AP) used in the management of schizophrenia. Although effective at reducing psychoses, APs cause rapid hyperglycemia, insulin resistance, and dyslipidemia, an effect mediated in part by glucagon. We tested if amylin, a hormone that reduces glucagon, or the amylin receptor agonist pramlintide would protect against acute olanzapine-induced impairments in glucose and lipid homeostasis alone or in combination with other glucose-lowering agents such as liraglutide. We demonstrated that pramlintide lowered olanzapine-induced increases in glucagon:insulin ratio with a trend to protect against excursions in blood glucose. There was an additive effect of pramlintide and liraglutide in protecting against olanzapine-induced hyperglycemia, which was mirrored by reductions in glucagon and attenuated markers of dyslipidemia. Our findings provide evidence that pramlintide, although moderately protective against some aspects of olanzapine-induced metabolic dysfunction, can be used to enhance the protective effects of other interventions against acute olanzapine-induced metabolic dysfunction.

Novel Approaches for the Management of Type 2 Diabetes Mellitus: An Update

Diabetes mellitus is an irreversible, chronic metabolic disorder indicated by hyperglycemia. It is now considered a worldwide pandemic. T2DM, a spectrum of diseases initially caused by tissue insulin resistance and slowly developing to a state characterized by absolute loss of secretory action of the β cells of the pancreas, is thought to be caused by reduced insulin secretion, resistance to tissue activities of insulin, or a combination of both. Insulin secretagogues, biguanides, insulin sensitizers, alpha-glucosidase inhibitors, incretin mimetics, amylin antagonists, and sodium-glucose co-transporter-2 (SGLT2) inhibitors are the main medications used to treat T2DM. Several of these medication's traditional dosage forms have some disadvantages, including frequent dosing, a brief half-life, and limited absorption. Hence, attempts have been made to develop new drug delivery systems for oral antidiabetics to ameliorate the difficulties associated with conventional dosage forms. In comparison to traditional treatments, this review examines the utilization of various innovative therapies (such as microparticles, nanoparticles, liposomes, niosomes, phytosomes, and transdermal drug delivery systems) to improve the distribution of various oral hypoglycemic medications. In this review, we have also discussed some new promising candidates that have been approved recently by the US Food and Drug Administration for the treatment of T2DM, like semaglutide, tirzepatide, and ertugliflozin. They are used as a single therapy and also as combination therapy with drugs like metformin and sitagliptin.

Efficacy of Fasting in Type 1 and Type 2 Diabetes Mellitus: A Narrative Review

Over the last decade, studies suggested that dietary behavior modification, including fasting, can improve metabolic and cardiovascular markers as well as body composition. Given the increasing prevalence of people with type 1 (T1DM) and type 2 diabetes mellitus (T2DM) and the increasing obesity (also in combination with diabetes), nutritional therapies are gaining importance, besides pharmaceutical interventions. Fasting has demonstrated beneficial effects for both healthy individuals and those with metabolic diseases, leading to increased research interest in its impact on glycemia and associated short- and long-term complications. Therefore, this review aimed to investigate whether fasting can be used safely and effectively in addition to medications to support the therapy in T1DM and T2DM. A literature search on fasting and its interaction with diabetes was conducted via PubMed in September 2022. Fasting has the potential to minimize the risk of hypoglycemia in T1DM, lower glycaemic variability, and improve fat metabolism in T1DM and T2DM. It also increases insulin sensitivity, reduces endogenous glucose production in diabetes, lowers body weight, and improves body composition. To conclude, fasting is efficient for therapy management for both people with T1DM and T2DM and can be safely performed, when necessary, with the support of health care professionals.

Early type 2 diabetes treatment intensification with glucagon-like peptide-1 receptor agonists in primary care: An Australian perspective on guidelines and the global evidence

Early and intensive management of type 2 diabetes has been shown to delay disease progression, reduce the risk of cardiorenal complications and prolong time to treatment failure. Glucagon-like peptide-1 receptor agonists (GLP-1RAs) are being increasingly recognized for their potential in early disease management, with recent guideline updates recommending second-line use of this injectable drug class alongside oral glucose-lowering drugs. GLP-1RAs target at least six of the eight core defects implicated in the pathogenesis of type 2 diabetes and offer significant glycaemic and weight-related improvements over other second-line agents in head-to-head trials. In addition, placebo-controlled clinical trials have shown cardiovascular protection with GLP-1RA use. Even so, this therapeutic class is underused in primary care, largely owing to clinical inertia and patient-related barriers to early intensification with GLP-1RAs. Fortunately, clinicians can overcome barriers to treatment acceptance through patient education and training, and management of treatment expectations. In this review we comment on global and Australian guideline updates and evidence in support of early intensification with this therapeutic class, and provide clinicians with practical advice for GLP-1RA use in primary care.

Enhancing endogenous levels of GLP1 dampens acute olanzapine induced perturbations in lipid and glucose metabolism

Olanzapine is a second-generation antipsychotic (SGA) used in the treatment of schizophrenia and several on- and off-label conditions. While effective in reducing psychoses, acute olanzapine treatment causes rapid hyperglycemia, insulin resistance, and dyslipidemia and these perturbations are linked to an increased risk of developing cardiometabolic disease. Pharmacological agonists of the glucagon-like peptide-1 (GLP1) receptor have been shown to offset weight-gain associated with chronic SGA administration and mitigate the acute metabolic side effects of SGAs. The purpose of this study was to determine if increasing endogenous GLP1 is sufficient to protect against acute olanzapine-induced impairments in glucose and lipid homeostasis. Male C57BL/6J mice were treated with olanzapine, in the absence or presence of an oral glucose tolerance test (OGTT), and a combination of compounds to increase endogenous GLP1. These include the non-nutritive sweetener allulose which acts to induce GLP1 secretion but not other incretins, the DPPiv inhibitor sitagliptin which prevents degradation of active GLP1, and an SSTR5 antagonist which relieves inhibition on GLP1 secretion. We hypothesized that this cocktail of agents would increase circulating GLP1 to supraphysiological concentrations and would protect against olanzapine-induced perturbations in glucose and lipid homeostasis. We found that 'triple treatment' increased both active and total GLP1 and protected against olanzapine-induced perturbations in lipid and glucose metabolism under glucose stimulated conditions and this was paralleled by an attenuation in the olanzapine induced increase in the glucagon:insulin ratio. Our findings provide evidence that pharmacological approaches to increase endogenous GLP1 could be a useful adjunct approach to reduce acute olanzapine-induced perturbations in lipid and glucose metabolism.

First-in-Class Oral Semaglutide: Overcoming Barriers of Incretinisation in the Indian Context

Despite the availability of multiple therapeutic options and strategies, patients with type 2 diabetes mellitus (T2DM) the world over have inadequate glycaemic control and India is no exception. Patients with T2DM in India have benefitted from glucagon-like peptide-1 analogues similar to that of patients from other parts of the world. However, subcutaneous treatment with glucagon-like peptide-1 receptor agonists (GLP-1 RAs) is limited by their injectable mode of administration. The present review highlights barriers to incretinisation with GLP-1RAs and the role of first-in-class oral semaglutide in the Indian context and provides guidance to physicians on its initiation and uses.

Glucagon-Like Peptide-1 Receptor Agonists and Brain Vascular Function

Prevention of cardiovascular events and regression of atherosclerotic changes are the primary aims of preventive cardiovascular medicine. Arterial thrombosis is caused by endothelial dysfunction, which disrupts vascular haemostasis. Glucagon-like peptide 1 (GLP-1) receptor agonists have been initially used as glucose lowering agents, but over time have been used for other indications due to their cardiorenal benefit, as well as their benefit in the regression of atherosclerosis process. The aim of this paper is to present the benefits of GLP-1 receptor agonists in the prevention of atherosclerotic changes, in the preservation of brain vascular function, and to show the possible role in the treatment of neurodegenerative diseases.

Weekly Semaglutide vs. Liraglutide Efficacy Profile: A Network Meta-Analysis

INTRODUCTION

Glucagon-like peptide 1 receptor agonist (GLP-1 RA) is a class of hypoglycemic medications. Semaglutide once-weekly (QW) and liraglutide once-daily (OD) significantly improved glycemic control compared to placebo. To date, no long-term phase III trials directly comparing semaglutide and liraglutide are available. This network meta-analysis (NMA) aims to compare the long-term efficacy of semaglutide and liraglutide.

METHODS

PubMed, Embase, and Cochrane Library were searched from inception until June 2019 to identify relevant articles. Nine long-term randomized controlled trials comparing once-weekly semaglutide or liraglutide with placebo or other active comparisons were identified. The outcomes of interest were changes in HbA1c and weight after 52 weeks. A Bayesian framework and NMA were used for data synthesis. This is a sub-study of the protocol registered in PROSPERO (number CRD42018091598).

RESULTS

The data showed significant superiority in HbA1c reduction of semaglutide 1 mg QW over liraglutide 1.2 and 1.8 mg with a treatment difference of 0.47% and 0.3%, respectively. Semaglutide 0.5 mg QW was found to be significantly superior to liraglutide 1.2 mg in HbA1c reduction with a treatment difference of 0.17%. Regarding weight reduction analysis, semaglutide 0.5 and 1 mg QW were significantly associated with a greater reduction than liraglutide 0.6 mg with a treatment difference of 2.42 and 3.06 kg, respectively. However, no significant reduction was found in comparison to liraglutide 1.2 and 1.8 mg.

CONCLUSIONS

Semaglutide improved the control of blood glucose and body weight. The capacity of long-term glycemic control and body weight control of semaglutide appears to be more effective than other GLP-1 RAs, including liraglutide. However, considering the number of included studies and potential limitations, more large-scale, head-to-head, well-designed randomized-controlled trials (RCTs) are needed to confirm these findings.

A GLP-1 Receptor Agonist Inhibits Aldosterone Release in Healthy Volunteers

Glucagon-like peptide 1 receptor agonists (GLP-1 RAs) are antidiabetic drugs with effects beyond antihyperglycemic action. The aim of the study was to examine whether a single dose of exenatide could be used as a stimulation test for the pituitary-adrenal axis. We carried out a single-group, open-label pilot clinical trial in an ambulatory setting. Ten healthy volunteers of both sexes with body weight>65 kg and age between 18-50 years were recruited. After fasting for 12 hours the subjects received 10 μg of exenatide solution subcutaneously. Blood samples were taken before the administration of exenatide and up to 150 minutes thereafter. The primary outcome was the maximal level of cortisol after the administration of exenatide. Single administration of exenatide 10 μg resulted in a modest increase in ACTH and cortisol levels, as compared to untreated values, and a decrease in blood glucose levels. Remarkably, a robust suppression of both renin and aldosterone levels occurred. We showed that acute administration of exenatide in a full therapeutic dose modestly stimulates the hypothalamic-pituitary-adrenal axis but inhibits the renin-aldosterone system. Further research is warranted to confirm this finding in the placebo-controlled study.

Cardiologist's approach to the diabetic patient: No further delay for a paradigm shift

Type 2 diabetes mellitus (DM) is constantly increasing worldwide and its most critical determinant of morbidity and mortality is still represented by cardiovascular (CV) complications. For years, cardiologists' approach to diabetic patients has been focused on risk factors optimization, with positive results. However, the management of DM per se was never truly considered in order to obtain prevention from major CV events, because medications used for glycemic control were not expected to gain CV benefit. Early trials concerning intensive versus conventional glycemia control did not prove useful in reducing the number of CV events. The introduction of new molecules led to a game change in DM treatment, as some new glucose-lowering drugs (GLDs), such as sodium-glucose linked transporter-2 inhibitors (SGLT-2i) and glucagon-like peptide 1 receptor agonists (GLP-1 RA), showed not only to be safe but also to ensure CV benefit. A combination of anti-atherogenic effects and hemodynamic improvements are likely explanations of the observed reduction of CV events and mortality. These evidence opened a completely new era in the field of GLDs and of DM treatment. Nonetheless, the presence of residual cardiovascular risk despite optimal medical therapy remains an issue and an aggressive strategy against multiple risk factors is suggested. A paradigm shift toward a new approach to DM management should be made with no further delay with the use of medications that may prevent CV events in an integrated strategy of CV risk reduction.

Efficacy and safety of glucagon-like peptide-1/glucagon receptor co-agonist JNJ-64565111 in individuals with type 2 diabetes mellitus and obesity: A randomized dose-ranging study

Weight loss has been shown to improve metabolic parameters and cardiovascular risk in people with type 2 diabetes mellitus (T2DM). This phase 2 study evaluated the safety and efficacy of JNJ-64565111, a dual agonist of GLP-1 and glucagon receptors, in individuals with T2DM and class II/III obesity. In this randomized, double-blind study, participants with T2DM (HbA1c 6.5%-9.5%), body mass index of 35 to 50 kg/m² and stable weight were randomly assigned (1:1:1:1) to placebo or JNJ-64565111 (5.0 mg, 7.4 mg or 10.0 mg). The primary endpoint was percent change from baseline in body weight at week 12. Of 195 dosed participants, 144 (73.8%) completed treatment. At week 12, placebo-subtracted body weight changes were -4.6%, -5.9% and -7.2% with JNJ-64565111 5.0 mg, 7.4 mg and 10.0 mg, respectively. All JNJ-64565111 doses were associated with no change in HbA1c and slight numerical elevation of fasting insulin. Numerical increases in fasting plasma glucose were observed with JNJ-64565111 5.0 mg and 7.4 mg. Incidence of treatment-emergent adverse events, especially nausea and vomiting, was higher with JNJ-64565111 vs placebo. Overall, JNJ-64565111 significantly reduced body weight in a dose-dependent manner vs placebo but was associated with greater incidence of treatment-emergent adverse events, no HbA1c reductions, and increased fasting plasma glucose and fasting insulin.

Exploring the recent molecular targets for diabetes and associated complications

Diabetes is likely one of the centenarian diseases which is apprehended with certainty to humans. According to established protocols of the World Health Organisation (WHO) and numerous investigated studies diabetes is analyzed as a stellar and leading health issue worldwide. Although, the implicit costs of this pathology are increasing every year, thus, there is a need to find a novel method which can provide promising results in the management of diabetes and can overcome the side effects associated with the conventional medication. Comprehensive review of this topic was undertaken through various research and review papers which were conducted using MEDLINE, BIOSIS and EMBASE database. Using various keywords, we retrieve the most relevant content for the thorough review on recent targets and novel molecular pathways for targeting diabetes and associated complications. From the detailed analysis, we have highlighted some molecular pathways and novel targets which had shown promising results in both in-vitro and in-vivo studies and may be considered as pipeline target for clinical trials. Furthermore, these targets not only abetted amelioration of diabetes but also helped in mitigation of diabetes associated complications as well. Thus, based on the available information and literature on these potential molecules, conclusive evidence can be drawn which confirms targeting these novel pathways may unleash an array of benefits that have the potential to overpower the benefits obtained from conventional therapy in the management of diabetes thereby decreasing morbidity and mortality associated with diabetic complications.

Pharmacokinetic and dose-finding studies on efpeglenatide in patients with type 2 diabetes

AIM

To assess the efficacy, safety and pharmacokinetic/pharmacodynamic properties of efpeglenatide, a long-acting glucagon-like peptide-1 receptor agonist, in patients with type 2 diabetes (T2D).

RESEARCH DESIGN AND METHODS

Two randomized, double-blind, placebo-controlled phase 2 trials were conducted. The single-dose study (n = 48) was a first-in-patient, sequential dose-escalation study. Patients received a single subcutaneous injection of efpeglenatide (2-100 μg/kg) or placebo. The repeated-dose study (n = 71) was a multiple-ascending-dose trial. Patients received weekly (1, 2 or 4 mg once weekly; 8-week period) or monthly (8, 12 or 16 mg once monthly; 9-week period) subcutaneous injections of efpeglenatide or placebo (without titration).

RESULTS

Both studies demonstrated dose-proportional increases in efpeglenatide serum concentrations. The median time to attain maximum serum concentration (t_max ) for efpeglenatide ranged from 72 to 144 hours in the single-dose study and from 48 to 120 hours in the repeated-dose study (following final dose). Geometric mean t_1/2 ranged from 135 to 180 hours across studies. Peak-to-trough ratios in the repeated-dose study ranged from 1.3 to 1.4 with once-weekly dosing and from 5.9 to 12.9 with once-monthly dosing. Following a single dose of efpeglenatide 14-100 μg/kg, fasting plasma glucose and postprandial plasma glucose levels were decreased at week 1 and remained below baseline levels for ≥3 weeks post-dosing. Repeated doses of efpeglenatide led to significant reductions in glycated haemoglobin vs placebo. In both studies, efpeglenatide was generally well tolerated. Gastrointestinal disorders were the most frequently reported treatment-emergent adverse events in efpeglenatide-treated patients.

CONCLUSIONS

The delayed t_max, long half-life, and low peak-to-trough ratios observed demonstrate potential for improved efficacy and dosing flexibility, with good tolerability of efpeglenatide in patients with T2D.

Discovery of LY3325656: A GPR142 agonist suitable for clinical testing in human

The discovery and optimization of a novel series of GPR142 agonists are described. These led to the identification of compound 21 (LY3325656), which demonstrated anti-diabetic benefits in pre-clinical studies and ADME/PK properties suitable for human dosing. Compound 21 is the first GPR142 agonist molecule advancing to phase 1 clinic trials for the treatment of Type 2 diabetes.

Stem-cell based organ-on-a-chip models for diabetes research

Diabetes mellitus (DM) ranks among the severest global health concerns of the 21st century. It encompasses a group of chronic disorders characterized by a dysregulated glucose metabolism, which arises as a consequence of progressive autoimmune destruction of pancreatic beta-cells (type 1 DM), or as a result of beta-cell dysfunction combined with systemic insulin resistance (type 2 DM). Human cohort studies have provided evidence of genetic and environmental contributions to DM; yet, these studies are mostly restricted to investigating statistical correlations between DM and certain risk factors. Mechanistic studies, on the other hand, aimed at re-creating the clinical picture of human DM in animal models. A translation to human biology is, however, often inadequate owing to significant differences between animal and human physiology, including the species-specific glucose regulation. Thus, there is an urgent need for the development of advanced human in vitro models with the potential to identify novel treatment options for DM. This review provides an overview of the technological advances in research on DM-relevant stem cells and their integration into microphysiological environments as provided by the organ-on-a-chip technology.

Liraglutide and Glycaemic Outcomes in the LEADER Trial

INTRODUCTION

The LEADER trial was a cardiovascular (CV) outcomes trial in patients with type 2 diabetes at high CV risk that compared liraglutide (n = 4668) with placebo (n = 4672) using a primary composite endpoint of 3-point major adverse CV events. The objective of this post hoc analysis was to investigate glycaemic outcomes across both treatment groups.

METHODS

Glycated haemoglobin (HbA_1c) was measured at randomisation, month 3, month 6 and every 6 months thereafter. Cox regression was used to analyse time to a composite endpoint of glycaemic deterioration, defined as a specified change in HbA_1c or a substantial intensification of insulin or oral antihyperglycaemic drug (OAD). The individual components of the composite were also analysed.

RESULTS

Baseline characteristics, including insulin and OAD use, were balanced between treatment groups. HbA_1c decreased from baseline in both groups, but the reduction was greater with liraglutide [estimated treatment difference at month 36: - 0.40%; 95% confidence interval (CI) - 0.45, - 0.34] despite the addition of more OADs and higher insulin use in the placebo group. Fewer of the patients treated with liraglutide (n = 3202, 68.6%) experienced glycaemic deterioration compared with those administered the placebo (n = 3988, 85.4%; average hazard ratio: 0.50; 95% CI 0.48, 0.53; p < 0.001). Analysis of the individual components showed similar results (both p  < 0.001).

CONCLUSIONS

Type 2 diabetes patients at high risk of CV events who were treated with liraglutide achieved greater reductions in HbA_1c, had a lower risk of hypoglycaemia and presented less glycaemic deterioration than similar patients who received the placebo. Nonetheless, progressive loss of glycaemic control occurred in both groups.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT01179048.

FUNDING

Novo Nordisk. Plain language summary available for this article.

Beyond Glucagon-like Peptide-1: Is G-Protein Coupled Receptor Polypharmacology the Path Forward to Treating Metabolic Diseases?

The glucagon-like peptide-1 receptor (GLP-1R) is a class B G-protein coupled receptor (GPCR) that has proven to be an effective target for developing medicines that treat type 2 diabetes mellitus (T2DM). GLP-1R agonists improve T2DM by enhancing glucose-stimulated insulin secretion, delaying gastric transit, decreasing glucagon levels, and reducing body weight due to anorexigenic actions. The therapeutic successes of these agents helped inspire the design of new multifunctional molecules that are GLP-1R agonists but also activate receptors linked to pathways that enhance insulin sensitization and/or energy expenditure. Herein, these agents are discussed in the context of polypharmacological approaches that may enable even further improvement in treatment outcomes. Moreover, we revisit classical polypharmaceutical GPCR approaches and how they may be utilized for treatment of T2DM. To determine optimal combination regimens, changes in drug discovery practices are likely needed because compensatory mechanisms appear to underlie progression of T2DM and limit the ability of current therapies to induce disease regression or remission.

Quality goal attainment and maintenance in patients with type II diabetes mellitus initiated on canagliflozin or a glucagon-like peptide-1 receptor agonist in an actual practice setting

OBJECTIVE

To compare achievement of quality goals (HbA1c, weight loss/body mass index [BMI], systolic blood pressure [SBP]), including maintaining HbA1c, between patients with type 2 diabetes mellitus (T2DM) treated with canagliflozin 300 mg (CANA) or a GLP-1 in an actual practice setting.

METHODS

Adults with T2DM newly initiated on CANA or a GLP-1 were identified from the IQVIA^TM Real-World Data Electronic Medical Records-US database (2012Q2-2016Q1). To account for differences in baseline characteristics, inverse probability of treatment weighting was used. Outcomes were compared using Cox models (hazard ratios [HRs] and 95% confidence intervals [CIs]) and Kaplan-Meier analyses.

RESULTS

CANA (n = 11,435) and GLP-1 (n = 11,582) cohorts had similar attainment of HbA1c < 8.0% (64 mmol/mol) and HbA1c < 9.0% (75 mmol/mol; HbA1c < 8.0%: HR [CI] = 0.98 [0.91-1.06]; HbA1c < 9.0%: HR [CI] = 1.02 [0.93-1.12]), while GLP-1 patients were 10% more likely to achieve HbA1c < 7.0% (53 mmol/mol). CANA and GLP-1 patients were similar in maintaining HbA1c < 7.0%, < 8.0%, or <9.0%, achieving weight loss ≥5% (HR [CI] = 1.05 [0.99-1.12]), achieving BMI <30 kg/m² (HR [CI] = 1.11 [0.98-1.27]), and achieving SBP <140 mmHg (HR [CI] = 1.07 [0.98-1.17]). CANA patients were 30% less likely to discontinue treatment, 28% less likely to have a prescription for a new anti-hyperglycemic, and 17-21% less likely to fail to maintain HbA1c < 8.0% or 9.0% or have a prescription for a new anti-hyperglycemic (composite outcome) vs GLP-1. No significant difference was observed for the composite outcome using the HbA1c < 7.0% threshold.

CONCLUSIONS

This retrospective study in an actual practice setting showed that CANA patients were generally as likely as GLP-1 patients to achieve HbA1c, weight, and blood pressure thresholds, and to maintain glycemic control while being less likely to discontinue treatment and/or have a new anti-hyperglycemic prescribed.

HBA1C CONTROL AND COST-EFFECTIVENESS IN PATIENTS WITH TYPE 2 DIABETES MELLITUS INITIATED ON CANAGLIFLOZIN OR A GLUCAGON-LIKE PEPTIDE 1 RECEPTOR AGONIST IN A REAL-WORLD SETTING

OBJECTIVE

To compare glycated hemoglobin (HbA1c) control and medication costs between patients with type 2 diabetes mellitus (T2DM) treated with canagliflozin 300 mg (CANA) or a glucagon-like peptide 1 receptor agonist (GLP-1 RA) in a real-world setting.

METHODS

Adults with T2DM newly initiated on CANA or a GLP-1 RA (index date) were identified from IQVIA^™ Real-World Data Electronic Medical Records U.S. database (March 29, 2012-April 30, 2016). Inverse probability of treatment weighting accounted for differences in baseline characteristics. HbA1c levels at 3-month intervals were compared using generalized estimating equations. Medication costs used wholesale acquisition costs.

RESULTS

For both cohorts (CANA: n = 11,435; GLP-1 RA: n = 11,582), HbA1c levels decreased at 3 months postindex and remained lower through 30 months. Absolute changes in mean HbA1c from index to 3 months postindex for CANA and GLP-1 RA were -1.16% and -1.21% (patients with baseline HbA1c ≥7% [53 mmol/mol]); -1.54% and -1.51% (patients with baseline HbA1c ≥8% [64 mmol/mol]); and -2.13% and -1.99% (patients with baseline HbA1c ≥9% [75 mmol/mol]), respectively. Postindex, CANA patients with baseline HbA1c ≥7% had similar HbA1c levels at each interval versus GLP-1 RA patients, except 9 months (mean HbA1c, 7.75% [61 mmol/mol] vs. 7.86% [62 mmol/mol]; P = .0305). CANA patients with baseline HbA1c ≥8% and ≥9% had consistently lower HbA1c numerically versus GLP-1 RA patients and statistically lower HbA1c at 9 (baseline HbA1c ≥8% or ≥9%), 27, and 30 months (baseline HbA1c ≥9%). Continuous 12-month medication cost $3,326 less for CANA versus GLP-1 RA.

CONCLUSION

This retrospective study demonstrated a similar evolution of HbA1c levels among CANA and GLP-1 RA patients in a real-world setting. Lower medication costs suggest CANA is economically dominant over GLP-1 RA (similar effectiveness, lower cost).

ABBREVIATIONS

AHA = antihyperglycemic agent BMI = body mass index CANA = canagliflozin 300 mg DCSI = diabetes complications severity index eGFR = estimated glomerular filtration rate EMR = electronic medical record GLP-1 RA = glucagon-like peptide 1 receptor agonist HbA1c = glycated hemoglobin ICD-9-CM = International Classification of Diseases-Ninth Revision-Clinical Modification ICD-10-CM = International Classification of Diseases-Tenth Revision-Clinical Modification IPTW = inverse probability of treatment weighting ITT = intent-to-treat MPR = medication possession ratio PDC = proportion of days covered PS = propensity score PSM = propensity score matching Quan-CCI = Quan-Charlson comorbidity index SGLT2 = sodium-glucose cotransporter 2 T2DM = type 2 diabetes mellitus WAC = wholesale acquisition cost.

The current state of GPCR-based drug discovery to treat metabolic disease

One approach of modern drug discovery is to identify agents that enhance or diminish signal transduction cascades in various cell types and tissues by modulating the activity of GPCRs. This strategy has resulted in the development of new medicines to treat many conditions, including cardiovascular disease, psychiatric disorders, HIV/AIDS, certain forms of cancer and Type 2 diabetes mellitus (T2DM). These successes justify further pursuit of GPCRs as disease targets and provide key learning that should help guide identifying future therapeutic agents. This report reviews the current landscape of GPCR drug discovery with emphasis on efforts aimed at developing new molecules for treating T2DM and obesity. We analyse historical efforts to generate GPCR-based drugs to treat metabolic disease in terms of causal factors leading to success and failure in this endeavour.

LINKED ARTICLES

This article is part of a themed section on Molecular Pharmacology of GPCRs. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v175.21/issuetoc.

Liraglutide protects cardiac function in diabetic rats through the PPARα pathway

Increasing evidence shows that diabetes causes cardiac dysfunction. We hypothesized that a glucagon-like peptide-1 analogue, liraglutide, would attenuate cardiac dysfunction in diabetic rats. Twenty-four Sprague Dawley (SD) rats were divided into 2 groups fed either a normal diet (normal, n = 6) or a high-fat diet (HFD, n = 18) for 4 weeks. Then, the HFD rats were injected with streptozotocin (STZ) to create a diabetic rat model. Diabetic rats were divided into 3 subgroups receiving vehicle (diabetic, n = 6), a low dose of liraglutide (Llirag, 0.2 mg/kg/day, n = 6) or a high dose of liraglutide (Hlirag, 0.4 mg/kg/day, n = 6). Metabolic parameters, systolic blood pressure, heart rate, left ventricular (LV) function, and whole genome expression of the heart were determined. Diabetic rats developed insulin resistance, increased blood lipid levels and oxidative stress, and impaired LV function, serum adiponectin, NO. Liraglutide improved insulin resistance, serum adiponectin, NO, heart rate and LV function and reduced blood triglyceride, total cholesterol levels and oxidative stress. Moreover, liraglutide increased heart Nr1h3 , Ppar-α and Srebp expression and reduced Dgat , and Angptl3 expression. Liraglutide prevented in cardiac dysfunction by activating the PPARα pathway to inhibit Dgat expression and oxidative stress in diabetic rats.

Real-world comparison of treatment patterns and effectiveness of albiglutide and liraglutide

Aim: To compare medication adherence, discontinuation and glycemic control in patients receiving albiglutide versus liraglutide. Patients & methods: Administrative claims data and glycated hemoglobin (HbA1c) results were analyzed from a sample of adult health plan members with Type 2 diabetes. Results: Patients were matched 1:1 in the albiglutide (n = 2213) and liraglutide (n = 2213) overall cohorts and in 244 patients with HbA1c results from each treatment group. Mean HbA1c change from baseline was −1.0% for both groups. At 6 months, mean ± standard deviation adherence was 0.69 ± 0.29 versus 0.64 ± 0.29 (p < 0.001), and discontinuation was 33.2 versus 37.8% (p = 0.002) with albiglutide versus liraglutide, but these were not statistically or clinically different at 12 months. Conclusion: Similar treatment patterns and clinically meaningful reductions in HbA1c were observed for both treatments in this real-world comparison.

Mechanisms to Elevate Endogenous GLP-1 Beyond Injectable GLP-1 Analogs and Metabolic Surgery

Therapeutic engineering of glucagon-like peptide 1 (GLP-1) has enabled development of new medicines to treat type 2 diabetes. These injectable analogs achieve robust glycemic control by increasing concentrations of "GLP-1 equivalents" (∼50 pmol/L). Similar levels of endogenous GLP-1 occur after gastric bypass surgery, and mechanistic studies indicate glucose lowering by these procedures is driven by GLP-1. Therefore, because of the remarkable signaling and secretory capacity of the GLP-1 system, we sought to discover mechanisms that increase GLP-1 pharmacologically. To study active GLP-1, glucose-dependent insulinotropic polypeptide receptor (Gipr)-deficient mice receiving background dipeptidyl peptidase 4 (DPP4) inhibitor treatment were characterized as a model for evaluating oral agents that increase circulating GLP-1. A somatostatin receptor 5 antagonist, which blunts inhibition of GLP-1 release, and agonists for TGR5 and GPR40, which stimulate GLP-1 secretion, were investigated alone and in combination with the DPP4 inhibitor sitagliptin; these only modestly increased GLP-1 (∼5-30 pmol/L). However, combining molecules to simultaneously intervene at multiple regulatory nodes synergistically elevated active GLP-1 to unprecedented concentrations (∼300-400 pmol/L), drastically reducing glucose in Gipr null and Lepr^db/db mice in a GLP-1 receptor-dependent manner. Our studies demonstrate that complementary pathways can be engaged to robustly increase GLP-1 without invasive surgical or injection regimens.

Use of Canagliflozin in Combination With and Compared to Incretin-Based Therapies in Type 2 Diabetes

In Brief Sodium-glucose cotransporter 2 (SGLT2) inhibitors and incretin-based therapies (dipeptidyl peptidase-4 [DPP-4] inhibitors and glucagon-like peptide-1 [GLP-1] receptor agonists) are widely used to treat patients with type 2 diabetes. In clinical and real-world studies, canagliflozin, an SGLT2 inhibitor, has demonstrated superior A1C lowering compared to the DPP-4 inhibitor sitagliptin. Canagliflozin can also promote modest weight/fat loss and blood pressure reduction. The addition of canagliflozin to treatment regimens that include a DPP-4 inhibitor or a GLP-1 receptor agonist has been shown to further improve glycemic control, while still maintaining beneficial effects on cardiometabolic parameters such as body weight and blood pressure. Overall, the available clinical and real-world evidence suggests that canagliflozin is a safe and well-tolerated treatment option that can be considered either in addition to or instead of incretin-based therapies for patients with type 2 diabetes.

Tolerance Does Not Develop Toward Liraglutide's Glucose-Lowering Effect

CONTEXT

Glucagon-like peptide-1 receptor agonists are popular antidiabetic drugs with potent glucose-lowering effects and low risk of hypoglycemia. Animal experiments and human data indicate that tolerance develops toward at least some of their effects (e.g., gastric motility). Whether tolerance develops toward the glucose-lowering effect of glucagon-like peptide-1 receptor agonists has never been formally tested.

OBJECTIVE

The objective of this pilot study was to test the hypothesis whether tolerance develops toward glucagon-like peptide-1 receptor agonists' glucose-lowering effect in chronic use.

DESIGN, SETTING, PARTICIPANTS, AND INTERVENTION

We conducted a single group, open-label clinical trial. Ten healthy volunteers were treated with 0.6 mg liraglutide once daily subcutaneously for 21 days. The drug's effect was quantified by serial graded glucose infusion tests, with glucose and c-peptide measured every 20 minutes and insulin secretion rate calculated.

MAIN OUTCOME MEASURE

The primary outcome was a change in the dose-response relationship between calculated insulin secretion rate and blood glucose level after acute and chronic administration of liraglutide.

RESULTS

Liraglutide clearly decreased the glucose values during the graded glucose infusion test and robustly enhanced insulin secretion. For all parameters, chronic liraglutide was as effective as acute treatment in human subjects.

CONCLUSIONS

We conclude that our results largely refute the hypothesis of tolerance development with prolonged liraglutide use in healthy nonobese humans.

Clinical Review of Antidiabetic Drugs: Implications for Type 2 Diabetes Mellitus Management

Type 2 diabetes mellitus (T2DM) is a global pandemic, as evident from the global cartographic picture of diabetes by the International Diabetes Federation (http://www.diabetesatlas.org/). Diabetes mellitus is a chronic, progressive, incompletely understood metabolic condition chiefly characterized by hyperglycemia. Impaired insulin secretion, resistance to tissue actions of insulin, or a combination of both are thought to be the commonest reasons contributing to the pathophysiology of T2DM, a spectrum of disease originally arising from tissue insulin resistance and gradually progressing to a state characterized by complete loss of secretory activity of the beta cells of the pancreas. T2DM is a major contributor to the very large rise in the rate of non-communicable diseases affecting developed as well as developing nations. In this mini review, we endeavor to outline the current management principles, including the spectrum of medications that are currently used for pharmacologic management, for lowering the elevated blood glucose in T2DM.

Treatment of Dyslipidemias to Prevent Cardiovascular Disease in Patients with Type 2 Diabetes

PURPOSE OF REVIEW

Current preventive and treatment guidelines for type 2 diabetes have failed to decrease the incidence of comorbidities, such as dyslipidemia and ultimately heart disease. The goal of this review is to describe the physiological and metabolic lipid alterations that develop in patients with type 2 diabetes mellitus. Questions addressed include the differences in lipid and lipoprotein metabolism that characterize the dyslipidemia of insulin resistance and type 2 diabetes mellitus. We also examine the relevance of the new AHA/ADA treatment guidelines to dyslipidemic individuals.

RECENT FINDINGS

In this review, we provide an update on the pathophysiology of diabetic dyslipidemia, including the role of several apolipoproteins such as apoC-III. We also point to new studies and new agents for the treatment of individuals with type 2 diabetes mellitus who need lipid therapies. Type 2 diabetes mellitus causes cardiovascular disease via several pathways, including dyslipidemia characterized by increased plasma levels of apoB-lipoproteins and triglycerides, and low plasma concentrations of HDL cholesterol. Treatments to normalize the dyslipidemia and reduce the risk for cardiovascular events include the following: lifestyle and medication, particularly statins, and if necessary, ezetimibe, to significantly lower LDL cholesterol. Other treatments, more focused on triglycerides and HDL cholesterol, are less well supported by randomized clinical trials and should be used on an individual basis. Newer agents, particularly the PCSK9 inhibitors, show a great promise for even greater lowering of LDL cholesterol, but we await the results of ongoing clinical trials.

Pharmacology and therapeutic implications of current drugs for type 2 diabetes mellitus

Type 2 diabetes mellitus (T2DM) is a global epidemic that poses a major challenge to health-care systems. Improving metabolic control to approach normal glycaemia (where practical) greatly benefits long-term prognoses and justifies early, effective, sustained and safety-conscious intervention. Improvements in the understanding of the complex pathogenesis of T2DM have underpinned the development of glucose-lowering therapies with complementary mechanisms of action, which have expanded treatment options and facilitated individualized management strategies. Over the past decade, several new classes of glucose-lowering agents have been licensed, including glucagon-like peptide 1 receptor (GLP-1R) agonists, dipeptidyl peptidase 4 (DPP-4) inhibitors and sodium/glucose cotransporter 2 (SGLT2) inhibitors. These agents can be used individually or in combination with well-established treatments such as biguanides, sulfonylureas and thiazolidinediones. Although novel agents have potential advantages including low risk of hypoglycaemia and help with weight control, long-term safety has yet to be established. In this Review, we assess the pharmacokinetics, pharmacodynamics and safety profiles, including cardiovascular safety, of currently available therapies for management of hyperglycaemia in patients with T2DM within the context of disease pathogenesis and natural history. In addition, we briefly describe treatment algorithms for patients with T2DM and lessons from present therapies to inform the development of future therapies.

Glucagon like peptide-1 receptor agonists may ameliorate the metabolic adverse effect associated with antiretroviral therapy

The number of people living with HIV and AIDS (PLWHA) reached to almost 40 million, half of which are under antiretroviral treatment (ART). Although the introduction of this therapy significantly improved the life span and quality of PLWHA, metabolic complications of these people remains to be an important issue. These metabolic complications include hyperlipidemia, abnormal fat redistribution and diabetes mellitus, which are defined as lipodystrophy syndrome. Glucagon-like peptide-1 (GLP-1) is a neuropeptide secreted from intestinal L cells and recently developed GLP-1 receptor agonists (GLP-1RAs) stimulate insulin secretion, improve weight control and reduce cardiovascular outcomes. This class of drugs may be a valuable medication in the treatment of HIV-associated metabolic adverse effects and extend the life expectancy of patients infected with HIV.

Common medications used by patients with type 2 diabetes mellitus: what are their effects on the lipid profile?

Dyslipidemia is the most fundamental risk factor for atherosclerotic cardiovascular disease (ASCVD). In clinical practice, many commonly prescribed medications can alter the patient's lipid profile and, potentially, the risk for ASCVD-either favorably or unfavorably. The dyslipidemia observed in type 2 diabetes mellitus (T2DM) can be characterized as both ominous and cryptic, in terms of unrecognized, disproportionately elevated atherogenic cholesterol particle concentrations, in spite of deceptively and relatively lower levels of low-density lipoprotein cholesterol (LDL-C). Several factors, most notably insulin resistance, associated with the unfavorable discordance of elevated triglyceride (TG) levels and low levels of high-density lipoprotein cholesterol (HDL-C), have been shown to correlate with an increased risk/number of ASCVD events in patients with T2DM. This review focuses on known changes in the routine lipid profile (LDL-C, TGs, and HDL-C) observed with commonly prescribed medications for patients with T2DM, including antihyperglycemic agents, antihypertensive agents, weight loss medications, antibiotics, analgesics, oral contraceptives, and hormone replacement therapies. Given that the risk of ASCVD is already elevated for patients with T2DM, the use of polypharmacy may warrant close observation of overall alterations through ongoing lipid-panel monitoring. Ultimately, the goal is to reduce levels of atherogenic cholesterol particles and thus the patient's absolute risk.

Glucagon-like peptide-1 agonists combating clozapine-associated obesity and diabetes

Clozapine is the most effective antipsychotic, but its use is tempered by adverse metabolic effects such as weight gain, glucose intolerance and type II diabetes. Current interventions do not facilitate compelling or sustained improvement in metabolic status. Recent studies suggest that glucagon-like peptide-1 (GLP-1) may play a key role in clozapine's metabolic effects, possibly suggesting that clozapine-associated obesity and diabetes are mediated independently through reduced GLP-1. As a result, GLP-1 agonists could show promise in reversing antipsychotic-induced metabolic derangements, providing mechanistic justification that they may represent a novel approach to treat, and ultimately prevent, both diabetes and obesity in patients on clozapine. GLP-1 agonists are already used for diabetes, and they provide a unique combination of glycaemic improvement and metabolically relevant weight loss in diabetic and non-diabetic patients, in the context of a currently favourable safety profile. Using GLP-1 agonists for clozapine-associated obesity and diabetes could be a potentially effective intervention that may reduce cardiometabolic morbidity and mortality in this vulnerable patient population.

Cardiovascular Effects of Incretin-Based Therapies

The incretin-based therapies, dipeptidyl peptidase-4 (DPP4) inhibitors and glucagon-like peptide-1 (GLP-1) analogs, are important new classes of therapy for type 2 diabetes mellitus (T2DM). These agents prolong the action of the incretin hormones, GLP-1 and glucose-dependent insulinotropic polypeptide (GIP), by inhibiting their breakdown. The incretin hormones improve glycemic control in T2DM by increasing insulin secretion and suppressing glucagon levels. The cardiovascular (CV) effects of the incretin-based therapies have been of substantial interest since 2008, when the US Food and Drug Administration began to require that all new therapies for diabetes undergo rigorous assessment of CV safety through large-scale CV outcome trials. This article reviews the most recent CV outcome trials of the DPP-4 inhibitors (SAVOR-TIMI 53, EXAMINE, and TECOS) as evidence that the incretin-based therapies have acceptable CV safety profiles for patients with T2DM. The studies differ with regard to patient population, trial duration, and heart failure outcomes but show similar findings for CV death, nonfatal myocardial infarction, and stroke, as well as hospitalization for unstable angina.

Treatment potential of the GLP-1 receptor agonists in type 2 diabetes mellitus: a review

Over the last decade, the discovery of glucagon-like peptide 1 receptor agonists (GLP-1 RAs) has increased the treatment options for patients with type 2 diabetes mellitus (T2DM). GLP-1 RAs mimic the effects of native GLP-1, which increases insulin secretion, inhibits glucagon secretion, increases satiety and slows gastric emptying. This review evaluates the phase III trials for all approved GLP-1 RAs and reports that all GLP-1 RAs decrease HbA1c, fasting plasma glucose, and lead to a reduction in body weight in the majority of trials. The most common adverse events are nausea and other gastrointestinal discomfort, while hypoglycaemia is rarely reported when GLP-1 RAs not are combined with sulfonylurea or insulin. Treatment options in the near future will include co-formulations of basal insulin and a GLP-1 RA.

The value of short- and long-acting glucagon-like peptide-1 agonists in the management of type 2 diabetes mellitus: experience with exenatide

BACKGROUND

Only about half of patients with type 2 diabetes treated with antihyperglycemic drugs achieve glycemic control (HbA1c <7%), most commonly due to poor treatment adherence. Glucagon-like peptide-1 (GLP-1) receptor agonists act on multiple targets involved in glucose homeostasis and have a low risk of causing hypoglycemia. While GLP-1 receptor (GLP-1R) agonists share the same mechanism of action, clinical profiles of individual agents differ, particularly between short- and long-acting agents. In this article, recent findings regarding the pharmacology of GLP-1 agonists are reviewed, and the clinical effects of short- versus long-acting agents are compared.

DATA SOURCES

Relevant articles were identified through a search of PubMed using the keywords glucagon-like peptide-1, GLP-1, glucagon-like peptide-1 receptor agonist, GLP-1R agonist, and exenatide for publications up to 22 May 2015. Supporting data were obtained from additional searches for albiglutide, dulaglutide, liraglutide and lixisenatide as well as from the bibliographies of key articles.

FINDINGS

Short-acting GLP-1R agonists produce greater reductions in postprandial glucose levels by slowing gastric emptying, whereas long-acting GLP-1R agonists produce greater reductions in fasting blood glucose by stimulating insulin secretion from the pancreas. These characteristics can be exploited to provide individualized treatment to patients. A large body of evidence supports the benefits of short- and long-acting exenatide as add-on therapy in patients with inadequate glycemic control despite maximum tolerated doses of metformin and/or sulfonylurea. Exenatide is generally well tolerated and no new safety concerns were identified during long-term follow-up of up to 5 years. A limitation of this review of short-and long-acting GLP-1 receptor agonists is that it focuses on exenatide rather than all the drugs in this class. However, the focus on a single molecule helps to avoid any confusion that may be introduced as a result of differences in molecular structure and size.

CONCLUSIONS

Short-acting GLP-1R agonists including exenatide are well suited to patients with type 2 diabetes with exaggerated postprandial glucose excursions and for co-administration with basal insulin therapy. Long-acting GLP-1R agonists including once weekly exenatide offer greater convenience and are well suited to patients who require specific control of fasting hyperglycemia.

The treatment of diabetes mellitus of patients with chronic liver disease

About 80% of patients with liver cirrhosis may have glucose metabolism disorders, 30% show overt diabetes mellitus (DM). Prospective studies have demonstrated that DM is associated with an increased risk of hepatic complications and death in patients with liver cirrhosis. DM might contribute to liver damage by promoting inflammation and fibrosis through an increase in mitochondrial oxidative stress mediated by adipokines. Based on the above mentioned the effective control of hyperglycemia may have a favorable impact on the evolution of these patients. However, only few therapeutic studies have evaluated the effectiveness and safety of antidiabetic drugs and the impact of the treatment of DM on morbidity and mortality in patients with liver cirrhosis. In addition, oral hypoglycemic agents and insulin may produce hypoglycemia and lactic acidosis, as most of these agents are metabolized by the liver. This review discusses the clinical implications of DM in patients with chronic liver disease. In addition the effectiveness and safety of old, but particularly the new antidiabetic drugs will be described based on pharmacokinetic studies and chronic administration to patients. Recent reports regarding the use of the SGLT2 inhibitors as well as the new incretin-based therapies such as injectable glucagon-like peptide-1 (GLP-1) receptor agonists and oral inhibitors of dipeptidylpeptidase-4 (DPP-4) will be discussed. The establishment of clear guidelines for the management of diabetes in patients with CLD is strongly required.

Treatment of clozapine-associated obesity and diabetes with exenatide (CODEX) in adults with schizophrenia: study protocol for a pilot randomised controlled trial

BACKGROUND

Clozapine causes significant metabolic disturbances including obesity and type 2 diabetes. Recent evidence that reduced glucagon-like-peptide-1 (GLP-1) may contribute to aetiology of clozapine-associated metabolic dysregulation suggests a potential therapeutic role for GLP-1 agonists.

METHOD

This open-label, pilot randomised controlled trial evaluates the effect of exenatide in clozapine-treated obese adults who have schizophrenia, with or without poorly controlled diabetes. Sixty out-patients will be randomised to once weekly extended release exenatide or treatment as usual for 24 weeks.

AIMS

To evaluate the feasibility of larger studies regarding methodology, acceptability, tolerability and estimate efficacy for glycaemic control or weight loss. Secondary outcomes are psychosis severity and metabolic parameters.

CONCLUSIONS

This is the first trial investigating GLP-1 agonists for glycaemic control and weight loss in clozapine-treated patients with either diabetes or obesity. Clozapine-associated obesity and diabetes with exenatide (CODEX) will provide proof-of-concept empirical evidence addressing whether this novel treatment is practical and worthy of further investigation.

DECLARATION OF INTEREST

A.W.R. has received speaker honoraria and travel grants from AstraZeneca, BoehringerIngelheim, Eli Lilly, MSD, Novo Nordisk and Sanofi and has participated on advisory panels for MSD and Novo Nordisk.

COPYRIGHT AND USAGE

© The Royal College of Psychiatrists 2015. This is an open access article distributed under the terms of the Creative Commons Non-Commercial, No Derivatives (CC BY-NC-ND) licence.

Protective effects of extendin‑4 on hypoxia/reoxygenation‑induced injury in H9c2 cells

Glucagon-like peptide-1 (GLP-1) analogues are likely to exert cardioprotective effects via balancing the energy metabolism in cardiomyocytes following ischemic or hypoxic insults. The present study aimed to explore the protective effects and mechanism of exendin-4, a GLP-1 analogue, on cardiomyocyte glucose uptake using an in vitro model of hypoxia/reoxygenation (H/R) of H9c2 cardiomyocyte cells. Pre-treatment with exendin-4 (200 nM) prior to H/R increased the cell viability, decreased cell apoptosis, enhanced cardiomyocyte glucose uptake and increased the production of adenosine triphosphate. Exendin-4 also decreased the levels of lactate dehydrogenase and creatine kinase-MB in the culture medium. Furthermore, the activity of carnitine palmitoyltransferase-1 in the H9c2 cells was decreased, while the activity of phosphofructokinase-1 was increased following exendin-4 treatment. Moreover, pre-treatment with exendin-4 increased the expression of p38 mitogen-activated protein kinase (p38MAPK) γ and translocation of glucose transporter-1 in H9c2 cells subjected to H/R. However, these effects were attenuated by the p38MAPK inhibitors BIRB796 and SB203580. The results suggested that exendin-4 exerted significant cardioprotective effects against H/R-induced cell injury and restored the metabolic imbalance of cardiomyocytes by activating the p38MAPK signaling pathway in the H9c2 cell model. Importantly, p38MAPKγ, one subunit of p38MAPK, may have the most important function in this process. The results of the present study may be helpful in the development of novel drugs to treat patients with coronary heart disease.