Chronic GLP-1 receptor activation by exendin-4 induces expansion of pancreatic duct glands in rats and accelerates formation of dysplastic lesions and chronic pancreatitis in the Kras(G12D) mouse model

Incretin mimetics and acute pancreatitis: enemy or innocent bystander?

PURPOSE OF REVIEW

The incretin enhancers and mimetics, including dipeptidyl peptidase-4 (DPP-4) inhibitors, GLP-1 receptor agonists (GLP-1RA) and GLP-1/GIP co-agonists, have become mainstays in the treatment of type 2 diabetes (T2D). Recently, the approval of certain GLP-1RA and GLP-1/GIP co-agonists for the treatment of obesity has broadened their popularity and use. In this review, we summarize the evidence for an association of these drugs with acute pancreatitis and other adverse events of special interest to gastroenterologists.

RECENT FINDINGS

In addition to pancreatic islets, GLP-1 receptors are expressed in the exocrine cells of the pancreas. There is inconsistent evidence for an association of DPP-4 inhibitors, GLP-1RA and co-agonists with risk for acute pancreatitis in individual trials. Meta-analyses of long-term randomized controlled trials indicate a small risk of acute pancreatitis associated with DPP-4 inhibitors but not GLP-1RA or co-agonists. Cholecystitis and cholelithiasis may be more common among those treated with GLP-1RA and GLP-1/GIP co-agonists. There is no evidence that any of these drugs are associated with an increased risk of pancreatic cancer.

SUMMARY

While drugs that leverage the incretin system are increasingly being used for patients with T2D and obesity, caution in warranted in those with a history of pancreatitis and gallbladder disease.

GLP-1 mimetics and diabetic ketoacidosis: possible interactions and clinical consequences

Diabetic ketoacidosis is a serious diabetes-related consequence that occurs in type 1 diabetes and less commonly in type 2 diabetes and is a major cause of death. It results from the metabolic consequences due to a lack of insulin secretion or impaired insulin activity in diabetes leading to dysregulated pathophysiologic pathways resulting in excessive ketone body formation. While ketone bodies are physiologic molecules, their high levels reduce the physiological pH of the blood and induce ketoacidosis, leading to increasing metabolic dysfunction. Glucagon-like peptide-1 (GLP-1) mimetics are a class of recently developed diabetes therapy that do not lead to hypoglycemic, but some reports have suggested a relationship between GLP-1 mimetics and ketogenesis. To clarify the possible interactions between GLP-1 mimetics and ketogenesis in diabetes, this review was undertaken to collate and interpret the literature.

Pancreatitis and Pancreatic Cancer Risk Among Patients With Type 2 Diabetes Receiving Dipeptidyl Peptidase 4 Inhibitors: An Updated Meta-Analysis of Randomized Controlled Trials

PURPOSE

This meta-analysis sought to assess the relationship between dipeptidyl peptidase-4 inhibitors (DPP-4) and the risk of pancreatitis and pancreatic cancer by synthesizing data from randomized, controlled trials, in light of the conflicting findings from observational studies and previous meta-analyses.

METHODS

Cochrane, Embase, ClinicalTrials.gov, and PubMed databases that compared the use of DPP-4 inhibitors and that reported pancreatitis and pancreatic cancer events in patients with diabetes mellitus Type 2 (T2DM) were searched using specific terms. Studies were included if they satisfied the following inclusion criteria: They were randomized trials comparing DPP-4 inhibitors use in patients with T2DM; The study's duration was longer than 24 weeks; And they reported pancreatitis and pancreatic cancer events. Stata 15 MP was used to analyze the data, and odds ratios (OR) with 95% confidence intervals (CI) were used to represent the results.

FINDINGS

A total of 81,737 participants with T2DM were included in the analysis. The results showed that during a mean follow-up period of 24 to 520 weeks, The use of DPP-4 inhibitors was not associated with an increased risk of pancreatitis (Peto-OR 0.97; 95% CI: 0.74, 1.27) or pancreatic cancer (Peto-OR = 0.88; 95% CI: 0.59, 1.30).

IMPLICATIONS

Current evidence fails to validate a significant correlation between DPP-4 therapy and pancreatitis or pancreatic cancer. However, subgroup analyses showed that sitagliptin was associated with a significant reduction in pancreatitis risk compared to the control group; furthermore, when comparing different types of control medications, a significant decrease in pancreatic cancer risk was observed among DPP-4 users compared to GLP-1 users.

Weight-centric prevention of cancer

Background

The link between excess adiposity and carcinogenesis has been well established for multiple malignancies, and cancer is one of the main contributors to obesity-related mortality. The potential role of different weight-loss interventions on cancer risk modification has been assessed, however, its clinical implications remain to be determined. In this clinical review, we present the data assessing the effect of weight loss interventions on cancer risk.

Methods

In this clinical review, we conducted a comprehensive search of relevant literature using MEDLINE, Embase, Web of Science, and Google Scholar databases for relevant studies from inception to January 20, 2024. In this clinical review, we present systematic reviews and meta-analysis, randomized clinical trials, and prospective and retrospective observational studies that address the effect of different treatment modalities for obesity in cancer risk. In addition, we incorporate the opinions from experts in the field of obesity medicine and oncology regarding the potential of weight loss as a preventative intervention for cancer.

Results

Intentional weight loss achieved through different modalities has been associated with a reduced cancer incidence. To date, the effect of weight loss on the postmenopausal women population has been more widely studied, with multiple reports indicating a protective effect of weight loss on hormone-dependent malignancies. The effect of bariatric interventions as a protective intervention for cancer has been studied extensively, showing a significant reduction in cancer incidence and mortality, however, data for the effect of bariatric surgery on certain specific types of cancer is conflicting or limited.

Conclusion

Medical nutrition therapy, exercise, antiobesity medication, and bariatric interventions, might lead to a reduction in cancer risk through weight loss-dependent and independent factors. Further evidence is needed to better determine which population might benefit the most, and the amount of weight loss required to provide a clinically significant preventative effect.

Challenges of Managing Type 3c Diabetes in the Context of Pancreatic Resection, Cancer and Trauma

Type 3c diabetes mellitus (T3cDM), also known as pancreatogenic or pancreoprivic diabetes, is a specific type of DM that often develops as a result of diseases affecting the exocrine pancreas, exhibiting an array of hormonal and metabolic characteristics. Several pancreatic exocrine diseases and surgical procedures may cause T3cDM. Diagnosing T3cDM remains difficult as the disease characteristics frequently overlap with clinical presentations of type 1 DM (T1DM) or type 2 DM (T2DM). Managing T3cDM is likewise challenging due to numerous confounding metabolic dysfunctions, including pancreatic endocrine and exocrine insufficiencies and poor nutritional status. Treatment of pancreatic exocrine insufficiency is of paramount importance when managing patients with T3cDM. This review aims to consolidate the latest information on surgical etiologies of T3cDM, focusing on partial pancreatic resections, total pancreatectomy, pancreatic cancer and trauma.

An Assessment of Semaglutide Safety Based on Real World Data: From Popularity to Spontaneous Reporting in EudraVigilance Database

Some glucagon-like peptide-1 receptor agonists (GLP-1 RAs), first used in the treatment of type 2 diabetes mellitus (T2DM), have been approved for the treatment of obesity in patients with or without T2DM (liraglutide-LIR, semaglutide-SEM, and tirzepatide-TIR). Social media had an important influence on the off-label use of GLP-1 RAs for obesity, especially for SEM. We analyzed the Google queries related to SEM to assess people's interest in this drug. We also investigated the occurrence of adverse drug reactions (ADRs) by searching the EudraVigilance database (EV) for Individual Case Safety Reports (ICSRs) that reported SEM as the suspected drug and performed a descriptive and a disproportionality analysis. The data obtained for SEM were compared to other GLP-1 RAs. SEM had the highest proportions of searches on Google associated with the term "weight loss" and presented the lowest number of severe ADRs, but it also had the highest number of ICSRs reported in EV. Even though no unexpected safety issues have been reported for it until now, SEM has a hi3gh tendency for overdose reports. The most frequent off-label use was reported for SEM and TIR. In order to lower the risks of ADRs, the off-label use should be reduced and carefully monitored.

Incretin-based drugs decrease the incidence of prostate cancer in type 2 diabetics: A pooling-up analysis

Incretin-based drugs, a class of Antidiabetic medications (ADMs) used in the treatment of type 2 diabetes, may affect the incidence of prostate cancer (PCa). But real-world evidence for this possible effect is lacking. Therefore, the aim of this study is to assess the effect of incretin-based drugs on the incidence of PCa, including glucagon-like peptide-1 (GLP-1) receptor agonists and dipeptidyl peptidase-4 (DPP-4) inhibitors. We searched PubMed, Embase, and Cochrane Library databases for eligible studies through September 2023. Two independent reviewers performed screening and data extraction. We used the Cochrane Handbook for Systematic Reviews and the Newcastle-Ottawa Scale (NOS) to assess the quality of included randomized controlled trials (RCTs) and cohort studies. We did a meta-analysis of available trial data to calculate overall risk ratios (RRs) for PCa. A total of 1238 articles were identified in our search. After screening for eligibility, 7 high-quality studies met the criteria for meta-analysis, including 2 RCTs and 5 cohort studies, with a total of 1165,738 patients. Compared with the control group, we found that incretin-based drugs reduced the relative risk of PCa by 35% (95% confidence interval (CI), 0.17-0.49; P = .0006). In subgroup analysis, the RR values for GLP-1 receptor agonists and DPP-4 inhibitors were 62% (95% CI, 0.45-0.85; P = .003) and 72% (95% CI, 0.46-1.12; P = .14), respectively. Incretin-based drugs are associated with lower incidence of prostate cancer and may have a preventive effect on prostate cancer in patients with type 2 diabetes.

Semaglutide in Cardiometabolic Diseases: SELECTing the Target Population

Cardiovascular diseases remain the main cause of death and disability worldwide. Despite the tremendous improvement in pharmacological, minimally invasive and rehabilitative strategies, global deaths due to cardiovascular diseases are still increasing. Additional risk factors have been recently proposed, and thanks to scientific progress, novel drugs for the control of the main risk factors focusing on the cardiometabolic pathways have been identified. Glucagon-like peptide-1 (GLP-1) receptor agonists represent an innovative step in the management of patients affected by type 2 diabetes mellitus. In addition to their significant efficacy on glycemic homeostasis, some members of this class of drugs have indications in the treatment of obesity. Furthermore, accumulated evidence in the literature has finally suggested a protective role in cardiovascular health. The possible role of GLP-1R agonist drugs (GLP-1RAs) on the mechanisms underlying chronic inflammation and the almost ubiquitous distribution of GLP-1 receptors could explain the enormous versatility of these drugs. Semaglutide is a GLP-1RA recently proven to be effective in cardiovascular outcomes. In the present article, we will review the available data on semaglutide in light of the most recent publications to better characterize the target population achieving cardiovascular benefits.

Cancer biology in diabetes update: Focusing on antidiabetic drugs

The association of type 2 diabetes with certain cancer risk has been of great interest for years. However, the effect of diabetic medications on cancer development is not fully understood. Prospective clinical trials have not elucidated the long-term influence of hypoglycemic drugs on cancer incidence and the safety for cancer-bearing patients with diabetes, whereas numerous preclinical studies have shown that antidiabetic drugs could have an impact on carcinogenesis processes beyond the glycemic control effect. Because there is no evidence of the safety profile of antidiabetic agents on cancer biology, careful consideration would be required when prescribing any medicines to patients with diabetes and existing tumor. In this review, we discuss the potential influence of each diabetes therapy in cancer 'initiation', 'promotion' and 'progression'.

Role of SGLT2 Inhibitors, DPP-4 Inhibitors, and Metformin in Pancreatic Cancer Prevention

Pancreatic carcinoma is a highly aggressive tumor that usually presents when it has already metastasized. Therapeutic options for cure remain scarce and rely on combination chemotherapy with limited sustainability. Diabetes is considered an important risk factor for the development of pancreatic cancer due to the production of proinflammatory cytokines, which result in increased cell proliferation. More than half of patients diagnosed with pancreatic cancer eventually develop diabetes due to the destruction of insulin-producing cells. The interlinkage of both diseases might identify a possible preventative strategy for reducing the incidence of pancreatic carcinoma. This study reviewed the recent literature on the association between pancreatic cancer risk and SGLT2 inhibitors, GLP-1 RA, DPP-4 inhibitors, and biguanides. There are mixed data regarding the relationship between GLP-1 RA and DPP-4 inhibitors and pancreatic cancer, with some trials suggesting that they might increase the risk. In contrast, studies have mostly revealed that SGLT2 inhibitors have an antiproliferative effect on various tumors, such as liver, pancreatic, prostate, bowel, lung, and breast carcinoma, which might be due to their mechanism of blockage of reabsorption of glucose by cells, lowering the amount of available glucose for the growth of tumor cells. Metformin, the first-line agent for diabetes, has also been shown to be associated with decreasing pancreatic cancer risk and improving prognosis in those who already have the disease. Dedicated trials are needed to further delineate the association of antidiabetic drugs with the risk of pancreatic cancer in the general population, as previous studies have mostly focused on diabetic patients.

Obesity, diabetes, and cancer: epidemiology, pathophysiology, and potential interventions

The proportion of deaths attributable to cancer is rising, and malignant neoplasms have become the leading cause of death in high-income countries. Obesity and diabetes are now recognized as risk factors for several types of malignancies, especially endometrial, colorectal, and postmenopausal breast cancers. Mechanisms implicated include disturbances in lipid-derived hormone secretion, sex steroids biosynthesis, hyperinsulinemia, and chronic inflammation. Intentional weight loss is associated with a mitigation of risk for obesity-related cancers, a phenomenon observed specially with bariatric surgery. The impact of pharmacological interventions for obesity and diabetes is not uniform: while metformin seems to protect against cancer, other agents such as lorcaserin may increase the risk of malignancies. However, these interpretations must be carefully considered, since most data stem from bias-prone observational studies, and high-quality randomized controlled trials with appropriate sample size and duration are needed to achieve definite conclusions. In this review, we outline epidemiological and pathophysiological aspects of the relationship between obesity, diabetes, and malignancies. We also highlight pieces of evidence regarding treatment effects on cancer incidence in these populations.

Necrotizing Pancreatitis Secondary to Hydrochlorothiazide and Alogliptin: A Case Report

Drug-induced pancreatitis occurs rarely but should be considered when more common causes have been ruled out. While simple to treat, mortality increases should it progress to a necrotizing process. Here, we present the case of a patient simultaneously using two drugs associated with pancreatitis, which we considered acted synergistically and consequently worsened the patient's outcome.

Mild Pancreatitis Induced by Linagliptin Revealed by a Medication Review

As dipeptidyl peptidase-4 inhibitors are becoming more utilized in the treatment of diabetes, it is important to recognize their side effects and become more familiar with them. As these side effects arise, physicians are more prepared to recognize and discontinue these medications. This case report describes a 34-year-old male who initially presented with a hemoglobin A1c greater than 16%. After titration of his diabetic medications, he presented with pancreatitis diagnosed by symptoms and imaging. Common causes of pancreatitis were ruled out, including biliary pathology, alcohol use, tobacco use, elevated calcium levels, and hypertriglyceridemia. The patient followed up in the clinic with persistent symptoms. A review of his medication list revealed pancreatitis as a side effect of linagliptin. After holding this medication, his symptoms improved over the course of a month.

A systematic review and meta-analysis of observational studies of the association between the use of incretin-based therapies and the risk of pancreatic cancer

BACKGROUND

Some early reports in the medical literature have raised concern about a possible increased risk of pancreatic cancer associated with the use of two broad classes of incretin-based therapies, dipeptidyl peptidase-4 inhibitors, and glucagon-like peptide-1 receptor agonists. This possibility has been somewhat mitigated by the null findings meta-analyses of randomized controlled trials, but the usefulness of their findings was hampered by serious shortcomings of lack of power and representativeness. These shortcomings can typically be addressed by observational studies, but observational studies on the topic have yielded conflicting findings. A systematic review and meta-analysis of observational studies was performed to qualitatively and quantitatively appraise the totality of evidence on the association between the use of incretin-based therapies and the risk of pancreatic cancer in routine clinical practice.

METHODS

The PubMed, Web of Science, Embase, and Google Scholar databases were searched. The study quality was appraised using the ROBINS-I tool and based on the presence of pharmacoepidemiology biases. A random-effects model was used to estimate the summary relative risks with corresponding CIs.

RESULTS

A total of 14 studies were included. The qualitative assessment revealed that all studies had inadequate follow-up (≤5 years), 12 studies were suspected to suffer from time-lag bias (due to inappropriate choice of comparator group) to varying extent, five studies included prevalent users, five studies did not implement exposure lag period, five studies had a serious risk of bias due to confounding, and one study had a time-window bias. The quantitative assessment showed no indication of an increased risk when all studies were pooled together (RR 1.04, 95% CI 0.87, 1.24) and when the analysis was restricted to the studies with the least bias (RR 0.77, 95% CI 0.51, 1.17). However, the pooled RRs were more frequently higher in the studies with less rigorous design and analysis. Specifically, a tendency toward an increased risk was observed in the studies with (RR 1.34, 95% CI 1.04, 1.72) or possibly with (RR 1.10, 95% CI 0.89, 1.36) time-lag bias, in the studies that did not apply (RR 1.23, 95% CI 0.93, 1.63) or with potentially inadequate exposure lag period of 6 months (RR 1.13, 95% CI 0.66, 1.94), in the studies that inappropriate comparator group of a combination of unspecified (RR 1.49, 95% CI 1.25, 1.78) or non-insulin (RR 1.15, 95% CI 0.93, 1.42) antidiabetic drugs, and in the studies with serious risk of bias due to confounding (RR 1.18, 95% CI 0.56, 2.49).

CONCLUSIONS

In summary, the totality of evidence from observational studies does not support the claim that the use of incretin-based therapies is associated with an increased risk of pancreatic cancer in routine clinical practice. The increased risk of pancreatic cancer observed in observational studies reflects bias resulting from suboptimal methodological approaches, which need to be avoided by future studies.

Glucagon-Like Peptide 1-Based Therapies and Risk of Pancreatic Cancer in Patients With Diabetes and Obesity

OBJECTIVES

There have been conflicting reports concerning an increased risk of pancreatic cancer (PC) in new users of glucagon-like peptide-1 agonists (GLP-1As). We aimed to explore whether the use of GLP-1A is associated with an increased risk of PC.

METHODS

A multicenter, retrospective cohort study was conducted using TriNetX. Adult patients with diabetes and/or overweight and obesity who were newly treated with GLP-1A or metformin for the first time between 2006 and 2021 were matched 1:1 using propensity score matching. The risk of PC was estimated using a Cox proportional hazards model.

RESULTS

A total of 492,760 patients were identified in the GLP-1A and 918,711 patients in the metformin group. After propensity score matching, both cohorts (370,490 each) were well matched. During follow-up, 351 patients in the GLP-1A and 956 on metformin developed PC after an exposure lag of 1 year. Glucagon-like peptide-1 agonists was associated with a significantly lower risk of PC (hazard ratio, 0.47; 95% confidence interval, 0.42-0.52).

CONCLUSIONS

The use of GLP-1A in patients with obesity/diabetes is associated with a lower risk of PC compared with a similar cohort of patients using metformin. Our study findings reassure clinicians and patients with apprehensions about any possible association between GLP-1A and PC.

GLP-1 receptor agonist-associated tumor adverse events: A real-world study from 2004 to 2021 based on FAERS

Background: GLP-1 receptor agonists (GLP-1RA) have demonstrated cardiovascular benefits, but the relationship between GLP-1RA and tumors is controversial. Recently, clinical trials reported higher rates of malignancy with semaglutide than control group. As real-world evidence of GLP-1RA-associated tumor risk is very limited, we explored the association of GLP-1RA and all types of neoplasms by mining the FDA Adverse Event Reporting System (FAERS) database. Methods: The FAERS data from the first quarter (Q1) of 2004 to the second quarter (Q2) of 2020 in the AERSMine were extracted to conduct disproportionality analysis, which was used by the proportional reporting ratio (PRR) to assess the relationship between GLP-1RA and all types of neoplasms. Then, the details of disproportionate GLP-1RA-associated tumor cases from Q1 2004 to Q2 2021 in the FAERS Public Dashboard were collected to analyze demographic characteristics. Results: A total of 8718 GLP-1RA-associated tumors were reported. Excluding cases with pre-existing tumors, other glucose-lowering drugs, and other GLP-1RA-related adverse events, diabetes cases with GLP-1RA as the main suspected drug were selected. GLP-1RA did not cause a disproportionate increase in all tumor cases (PRR 0.83) at the SOC level, and there was also no increase in most types of tumors associated with GLP-1RA at the HLGT/HLT levels. Significant signals were detected between GLP-1RA and certain tumors, including thyroid cancers [medullary thyroid cancer (PRR 27.43) and papillary thyroid cancer (PRR 8.68)], pancreatic neoplasms malignant (PRR 9.86), and islet cell neoplasms and APUDoma NEC (PRR 2.86). The combination of GLP-1RA with dipeptidyl-peptidase IV inhibitors (DPP4i) perhaps caused the increased reporting rate in some tumors. Conclusion: Our study provided new real-world evidence for oncology safety information of GLP-1RA. Given the wide use of GLP-1RA, clinicians should be well informed about important potential adverse events. Our pharmacovigilance analysis also prompted clinicians to raise concerns about potential tumor-related adverse effects when combining GLP-1RA with DPP4i.

Exocrine and Endocrine Inflammation Increases Cellular Replication in the Pancreatic Duct Compartment in Type 1 Diabetes

Context

We recently demonstrated increased cellular proliferation in the pancreatic ductal gland (PDG) compartment of organ donors with type 1 diabetes, suggesting that PDGs may harbor progenitor cells capable of pancreatic regeneration.

Objective

We evaluated the impact of diabetes and pancreatic inflammation on PDG and interlobular duct (ILD) cellular proliferation and profiles.

Methods

Endocrine hormone expression (insulin, glucagon, somatostatin, pancreatic polypeptide) and proliferating Ki67+ cells were localized within the PDG and ILD compartments by multicolor immunohistochemistry in cross-sections from the head, body, and tail regions of pancreata from those with (n = 31) or without type 1 diabetes (n = 43). Whole-slide scanned images were analyzed using digital pathology.

Results

Type 1 diabetes donors with insulitis or histologically identified pancreatitis had increased cellular replication in the ILD and PDG compartments. Interestingly, while cellular proliferation within the pancreatic ductal tree was significantly increased in type 1 diabetes (PDG mean = 3.36%, SEM = 1.06; ILD mean = 2.78%, SEM = 0.97) vs nondiabetes(ND) subjects without pancreatic inflammation (PDG mean = 1.18%, SEM = 0.42; ILD mean = 0.74%, SEM = 0.15, P < 0.05), robust replication was also observed in ND donors with pancreatitis (PDG mean = 3.52%, SEM = 1.33; ILD mean = 2.18%, SEM = 0.54, P < 0.05). Few polyhormonal cells were present in the ILD (type 1 diabetes = 0.04 ± 0.02%; ND = 0.08 ± 0.03%, P = 0.40) or PDG compartment (type 1 diabetes = 0.02 ± 0.01%; ND = 0.08 ± 0.13%, P = 0.63).

Conclusion

These data suggest that increased pancreatic ductal cell replication is associated with sustained pancreatic inflammation; however, as replicating cells were hormone-negative, PDGs do not appear to represent a compelling endogenous source of hormone-positive endocrine cells.

The Relationship Between Diabetes Mellitus and Cancers and Its Underlying Mechanisms

Epidemiological studies suggest associations between diabetes mellitus and some cancers. The risk of a number of cancers appears to be increased in diabetes mellitus. On the other hand, some cancer and cancer therapies could lead to diabetes mellitus. Genetic factors, obesity, inflammation, oxidative stress, hyperglycemia, hyperinsulinemia, cancer therapies, insulin and some oral hypoglycemic drugs appear to play a role in the crosstalk between diabetes mellitus and cancers. This review summarized the associations between various types of diabetes and cancers and updated available evidence of underlying mechanisms between diabetes and cancers.

Type 2 Diabetes Mellitus Intersects With Pancreatic Cancer Diagnosis and Development

The relationship between type 2 diabetes mellitus (T2DM) and pancreatic cancer (PC) is complex. Diabetes is a known risk factor for PC, and new-onset diabetes (NOD) could be an early manifestation of PC that may be facilitate the early diagnosis of PC. Metformin offers a clear benefit of inhibiting PC, whereas insulin therapy may increase the risk of PC development. No evidence has shown that novel hypoglycemic drugs help or prevent PC. In this review, the effects of T2DM on PC development are summarized, and novel strategies for the prevention and treatment of T2DM and PC are discussed.

Safety of Semaglutide

The glucagon-like peptide-1 receptor agonist (GLP-1RA) semaglutide is the most recently approved agent of this drug class, and the only GLP-1RA currently available as both subcutaneous and oral formulation. While GLP-1RAs effectively improve glycemic control and cause weight loss, potential safety concerns have arisen over the years. For semaglutide, such concerns have been addressed in the extensive phase 3 registration trials including cardiovascular outcome trials for both subcutaneous (SUSTAIN: Semaglutide Unabated Sustainability in Treatment of Type 2 Diabetes) and oral (PIONEER: Peptide InnOvatioN for the Early diabEtes tReatment) semaglutide and are being studied in further trials and registries, including real world data studies. In the current review we discuss the occurrence of adverse events associated with semaglutide focusing on hypoglycemia, gastrointestinal side effects, pancreatic safety (pancreatitis and pancreatic cancer), thyroid cancer, gallbladder events, cardiovascular aspects, acute kidney injury, diabetic retinopathy (DRP) complications and injection-site and allergic reactions and where available, we highlight potential underlying mechanisms. Furthermore, we discuss whether effects are specific for semaglutide or a class effect. We conclude that semaglutide induces mostly mild-to-moderate and transient gastrointestinal disturbances and increases the risk of biliary disease (cholelithiasis). No unexpected safety issues have arisen to date, and the established safety profile for semaglutide is similar to that of other GLP-1RAs where definitive conclusions for pancreatic and thyroid cancer cannot be drawn at this point due to low incidence of these conditions. Due to its potent glucose-lowering effect, patients at risk for deterioration of existing DRP should be carefully monitored if treated with semaglutide, particularly if also treated with insulin. Given the beneficial metabolic and cardiovascular actions of semaglutide, and the low risk for severe adverse events, semaglutide has an overall favorable risk/benefit profile for patient with type 2 diabetes.

Exploring the GLP-1-GLP-1R axis in porcine pancreas and gastrointestinal tract in vivo by ex vivo autoradiography

INTRODUCTION

Glucagon-like peptide-1 (GLP-1) increases insulin secretion from pancreatic beta-cells and GLP-1 receptor (GLP-1R) agonists are widely used as treatment for type 2 diabetes mellitus. Studying occupancy of the GLP-1R in various tissues is challenging due to lack of quantitative, repeatable assessments of GLP-1R density. The present study aimed to describe the quantitative distribution of GLP-1Rs and occupancy by endogenous GLP-1 during oral glucose tolerance test (OGTT) in pigs, a species that is used in biomedical research to model humans.

RESEARCH DESIGN AND METHODS

GLP-1R distribution and occupancy were measured in pancreas and gastrointestinal tract by ex vivo autoradiography using the GLP-1R-specific radioligand ¹⁷⁷Lu-exendin-4 in two groups of pigs, control or bottle-fed an oral glucose load. Positron emission tomography (PET) data from pigs injected with ⁶⁸Ga-exendin-4 in a previous study were used to retrieve data on biodistribution of GLP-1R in the gastrointestinal tract.

RESULTS

High homogenous uptake of ¹⁷⁷Lu-exendin-4 was found in pancreas, and even higher uptake in areas of duodenum. Low uptake of ¹⁷⁷Lu-exendin-4 was found in stomach, jejunum, ileum and colon. During OGTT, there was no increase in plasma GLP-1 concentrations and occupancy of GLP-1Rs was low. The ex vivo autoradiography results were highly consistent with to the biodistribution of ⁶⁸Ga-exendin-4 in pigs scanned by PET.

CONCLUSION

We identified areas with similarities as well as important differences regarding GLP-1R distribution and occupancy in pigs compared with humans. First, there was strong ligand binding in the exocrine pancreas in islets. Second, GLP-1 secretion during OGTT is minimal and GLP-1 might not be an important incretin in pigs under physiological conditions. These findings offer new insights on the relevance of porcine diabetes models.

Acute Pancreatitis Induced by Linagliptin: A Rare but Dangerous Side Effect

Diabetes mellitus type 2 (DMT2) is a highly prevalent disease both in the United States and worldwide. Multiple treatment options are currently available, and several new groups of medications have been introduced over the last couple of decades. One of these groups is dipeptidyl peptidase-4 (DPP-4) inhibitors. These medications have side effects, some of which are severe and potentially life-threatening; however, some of their side effects have been underreported since they are relatively new. When prescribing these medications, it is essential to be cautious, especially with patients at an increased risk of developing an adverse effect. We present the case of a 57-year-old male who developed DPP-4 inhibitor-induced acute pancreatitis after the initiation of linagliptin. The patient did not have any apparent risk factors for pancreatitis as he did not drink alcohol or smoke cigarettes, his lipid panel was within normal limits, and he had a cholecystectomy five years prior. His linagliptin was held in the hospital and discontinued post-discharge, which led to the resolution of his symptoms.

[Exenatide promotes cholesterol efflux in pancreatic tissue of obese diabetic rats]

OBJECTIVE

To study the effect of exenatide on the expression of ABCA1 and cholesterol metabolism in the pancreas of obese diabetic rats.

OBJECTIVE

Twenty-four normal male SD rats and 18 obese diabetic rats (induced by high-fat feeding and STZ injection) were both divided equally into 2 groups for injections of saline or exenatide. After treatment for a week, the expression of ABCA1, cholesterol metabolism, and islet function of the rats were examined using real-time PCR, Western blotting, oil red O staining, cholesterol content determination, and HE staining.

OBJECTIVE

The expressions of ABCA1 at both mRNA and protein levels in pancreatic tissue were significantly lower in obese diabetic rats than in normal SD rats. The obese diabetic rats showed obvious lipid deposition and increased cholesterol content in the pancreatic tissue with significantly reduced islet volume and structural changes (P < 0.05); exenatide treatment of the diabetic rats significantly up-regulated ABCA1 expression, reduced lipid deposition and cholesterol content in pancreatic tissue, and increased number and volume of the islets, which presented with more orderly alignment (P < 0.05).

OBJECTIVE

Obese diabetic rats have lowered ABCA1 expression, cholesterol efflux block, and cholesterol accumulation in the pancreatic tissue. Exenatide can up-regulate ABCA1 expression and promote cholesterol efflux to reduce cholesterol content in the pancreatic tissue and improve islet function in obese diabetic rats.

Emerging Roles of Dipeptidyl Peptidase-4 Inhibitors in Delaying the Progression of Type 1 Diabetes Mellitus

Type 1 diabetes mellitus (T1DM) results from the immune cell-mediated destruction of functional pancreatic β-cells. In the presymptomatic period, T1DM is characterized by the presence of two or more autoantibodies against the islet cells in patients without glycemic decompensation. Therapeutic strategies that can modify the autoimmune process could slow the progression of T1DM. Dipeptidyl peptidase-4 (DPP-4) or CD26, a multifunctional serine protease with a dual function (regulatory protease and binding protein), can modulate inflammation and immune cell-mediated β-cell destruction. CD26 is involved in T-cell co-stimulation, migration, memory development, thymic maturation, and emigration patterns. DPP-4 degrades the peptide hormones GLP-1 and GIP. In addition to regulating glucose metabolism, DPP-4 exerts anti-apoptotic, regenerative, and proliferative effects to promote β-cell mass expansion. GLP-1 receptor signaling may regulate murine lymphocyte proliferation and maintenance of peripheral regulatory T-cells. In patients with T1DM, the serum DPP-4 activity is upregulated. Several studies have suggested that the upregulated DPP-4 activity is correlated with T1DM pathophysiology. DPP-4, which is preferentially expressed on the Th1 surface, can promote the polarization of Th1 immunity, a prerequisite for T1DM development. CD26 inhibition can suppress T-cell proliferation and Th1 cytokine production and stimulate tumor growth factor beta-1 (TGF-β1) secretion, which plays an important role in the regulation of autoimmunity in T1DM. Studies on humans or animal models of T1DM have suggested that DPP-4 inhibitors can improve β-cell function and attenuate autoimmunity in addition to decreasing insulin dependence. This review summarizes the emerging roles of DPP-4 inhibitors in potentially delaying the progression of T1DM.

Glucagon-like peptide-1 receptor is expressed in human and rodent testis

BACKGROUND

The incretin hormone glucagon-like peptide-l (GLP-1) is an important regulator of post-prandial insulin secretion, acting through a G protein-coupled cell surface receptor (GLP-1R). In addition to its expression in pancreatic β-cells, several studies suggested that GLP-1R is located in extra-pancreatic tissues.

OBJECTIVES

In this study, we examined for the first time the testicular distribution of the GLP-1R, both in normal human and neoplastic testicular tissues as well as in rodent testis and rodent testicular cell lines.

METHODS AND METHODS

The GLP-1R distribution in testicular section has been evaluated by immunohistochemistry, the specificity of IHC was validated by demonstrating a positive staining for GLP-1RmRNA by RISH technology. While GLP-1R expression in terms of protein was detected by western blot analysis, Moreover, mRNA levels were determined in human testis, in rodent Leydig, and Sertoli cell lines.

RESULTS

Using immunohistochemistrya specific staining for GLP-1R was detected in Leydig cells. The specificity of IHC was validated by demonstrating a positive staining for GLP-1RmRNA only in these cell types. Species differences in the GLP-1R expression between humans and rodents were observed. Interestingly, a decreased expression of the receptor in rodent tumor Leydig cell line and an absence in human Leydig tumor samples was detected.

DISCUSSION

It may be hypothesized that GLP-1R acts like an oncosuppressor in Leydig tumors. A role in regulation of hormone secretion by GLP-1 has been shown in other endocrine cells, therefore we hypothesized that GLP-1R is able to modulate somehow the Leydig cell function.

CONCLUSION

In our findings, a careful evaluation of human testicular tissues and rodent testis revealed Leydig cells as a potential target for GLP-1. Collectively, an effect of GLP-1R in Leydig cell function may be presumed although future studies are needed to ascertain the GLP-1R's role both in normal and tumor Leydig cells.

Islet cell dysfunction in patients with chronic pancreatitis

Chronic pancreatitis (CP) is characterized by progressive inflammation and fibrosis of the pancreas that eventually leads to pancreatic exocrine and endocrine insufficiency. Diabetes in the background of CP is very difficult to manage due to high glycemic variability and concomitant malabsorption. Progressive beta cell loss leading to insulin deficiency is the cardinal mechanism underlying diabetes development in CP. Alpha cell dysfunction leading to deranged glucagon secretion has been described in different studies using a variety of stimuli in CP. However, the emerging evidence is varied probably because of dependence on the study procedure, the study population as well as on the stage of the disease. The mechanism behind islet cell dysfunction in CP is multifactorial. The intra-islet alpha and beta cell regulation of each other is often lost. Moreover, secretion of the incretin hormones such as glucagon like peptide-1 and glucose-dependent insulinotropic polypeptide is dysregulated. This significantly contributes to islet cell disturbances. Persistent and progressive inflammation with changes in the function of other cells such as islet delta cells and pancreatic polypeptide cells are also implicated in CP. In addition, the different surgical procedures performed in patients with CP and antihyperglycemic drugs used to treat diabetes associated with CP also affect islet cell function. Hence, different factors such as chronic inflammation, dysregulated incretin axis, surgical interventions and anti-diabetic drugs all affect islet cell function in patients with CP. Newer therapies targeting alpha cell function and beta cell regeneration would be useful in the management of pancreatic diabetes in the near future.

GLP-1 receptor agonists and pancreatic safety concerns in type 2 diabetic patients: data from cardiovascular outcome trials

PURPOSE

Glucagon-like peptide-1 receptor agonists (GLP-1RAs) have been suggested to be associated with an increased risk of pancreatitis and pancreatic cancer. The aim of this meta-analysis was to collect data from large-scale cardiovascular outcome trials (CVOTs) to assess the effect of GLP-1RAs on the incidence of acute pancreatitis and pancreatic cancer.

METHODS

Database of Medline, Embase, and the Cochrane Central Register of Controlled Trials were extensively searched up to October 10, 2019. Randomized controlled trials were eligible if they compared GLP-RA with placebo as add-on therapy to standard care in T2DM patients, and reported outcomes required for cardiovascular safety studies and events of acute pancreatitis and/or pancreatic cancer. Peto odds ratio (OR) with 95% confidence interval (CI) was calculated for acute pancreatitis and pancreatic cancer.

RESULTS

Seven CVOTs enrolling 56,004 patients with T2DM were identified, with a median follow-up time ranging from 1.3 to 5.4 years. A total of 180 cases of acute pancreatitis and 108 cases of pancreatic cancer were reported. The risk of either acute pancreatitis or pancreatic cancer with GLP-1-RA treatment was not significantly different from that observed in placebo arm (Peto OR [95% CI] 1.05 [0.78-1.40], P = 0.76, and 1.12 [0.77-1.63], P = 0.56, respectively), and the results remained robust to sensitivity analyses.

CONCLUSION

Pooled analysis of CVOTs did not suggest any increased risk of either acute pancreatitis or pancreatic cancer with GLP-1RA treatment in T2DM patients.

Glucagon from the phylogenetically ancient paddlefish provides a template for the design of a long-acting peptide with effective anti-diabetic and anti-obesity activities

This study has examined the in vitro and in vivo anti-diabetic properties of the peptidase-resistant analogues [D-Ser²]palmitoyl-paddlefish glucagon and [D-Ser²]palmitoyl-lamprey glucagon. The peptides stimulated insulin release from BRIN-BD11 clonal β-cells and isolated mouse pancreatic islets and also enhanced cAMP production in cells transfected with the human GLP-1 receptor and with the human glucagon receptor. The insulinotropic actions of the peptides were attenuated in INS-1 cells lacking GLP-1 and glucagon receptors. [D-Ser²]palmitoyl-paddlefish glucagon stimulated proliferation of BRIN-BD11 cells and protected against cytokine-mediated apoptosis as effectively as GLP-1. The analogue was more effective than the native peptide or the lamprey glucagon analogue in acutely lowering blood glucose and elevating plasma insulin in lean mice even when administered up to 4 h before a glucose load. Twice daily administration of [D-Ser²]palmitoyl-paddlefish glucagon to high-fat fed mice over 21 days reduced food intake, body weight, non-fasting blood glucose and plasma insulin concentrations, as well as significantly improving glucose tolerance and insulin resistance and decreasing α-cell area and pancreatic insulin content. Islet expression of the Gcgr, Glp1r, Gipr and Slc2a2 (GLUT-2) genes significantly increased. These data demonstrate that long-acting peptide [D-Ser²]palmitoyl-paddlefish glucagon exerts beneficial metabolic properties in diabetic mice via Ggcr- and Glp1r-activated pathways and so shows potential as a template for further development into an agent for treatment of patients with obesity-related Type 2 diabetes.

Risk of acute pancreatitis with incretin-based therapy: a systematic review and updated meta-analysis of cardiovascular outcomes trials

BACKGROUND

The link of acute pancreatitis (AP) with Incretin based therapies (IBTs) in type 2 diabetes has existed since United States Food and Drug Administration alert in 2010. This issue still remains unresolved due to conflicting results among studies.

RESEARCH DESIGN AND METHODS

We performed a systematic search of the PubMed, Embase, and Cochrane Library databases until 31 July 2019, and retrieved all cardiovascular outcome trials (CVOTs) of IBTs conducted for ≥12 months that reported the pre-specified and or pre-adjudicated pancreatitis outcomes. Subsequently, we conducted a meta-analysis to study the risk of AP observed with IBT in CVOTs.

RESULTS

A meta-analysis of seven CVOTs of GLP-1 receptor agonists (GLP-1RAs) compared with placebo (N = 55,932) found no significant increase in AP (odds ratio [OR], 1.05; 95% confidence interval [CI], 0.77-1.42; p = 0.77). In contrast, meta-analysis of five CVOTs comparing DPP-4 inhibitors with placebo (N = 47,714) and six CVOTs comparing DPP-4 inhibitors with placebo or active comparator (N = 53,747), found a significant increase (OR, 1.81; 95% CI, 1.21-2.70; p = 0.04 and OR, 1.54; 95% CI, 1.08-2.18; p = 0.02, respectively) in AP without any significant heterogeneity.

CONCLUSIONS

This meta-analysis revealed a significant association between pancreatitis and DPP-4 inhibitors; however, no such association was observed for GLP-1RAs.

The Relationship Between Dipeptidyl Peptidase-4 Inhibitor Usage and Asymptomatic Amylase Lipase Increment in Type 2 Diabetes Mellitus Patients

OBJECTIVES

In different studies, it has been shown that the use of dipeptidyl peptidase-4 (DPP-4) inhibitors (DPP-4 inh) does not increase the risk of pancreatitis or pancreatic cancer. Although the number of studies involving clinical pancreatitis clinics is sufficient, the number of studies involving clinical non-pancreatitis hyperamylasemia is rare. The aim of the study was to investigate the relationship between DPP-4 inh usage and amylase and lipase increment without clinical pancreatitis symptoms.

MATERIALS AND METHODS

Eighty-seven patients who met the inclusion criteria were enrolled. The patients were divided into 3 groups according to their use of saxagliptin, sitagliptin, or vildagliptin. All patients included in the study were receiving metformin at a dose of 2 g/day. Fasting blood glucose, postprandial blood glucose, HbA1C, serum creatinine, ALT, amylase, and lipase results were recorded at the beginning of treatment and at the end of 3 months.

RESULTS

There was an increase in all groups in terms of amylase and lipase values but there was no significant difference between the groups in terms of increase (p>0.05) There was no statistically significant increase in the saxagliptin and vildagliptin groups (p>0.05) when the baseline and 3-month values of lipase and amylase increase were examined. However, there was a statistically significant increase in amylase and lipase in the sitagliptin group (p<0.05).

CONCLUSION

The use of DPP-4 inh can increase amylase and lipase levels without clinical findings of acute pancreatitis in the patient. DPP-4 inh should be used with caution in patients at risk for pancreatitis and pancreatic cancer. Patients using DPP-4 inh, especially sitagliptin, should be evaluated carefully for pancreatitis risk factors.

Pancreatitis and pancreatic cancer in patientes treated with Dipeptidyl Peptidase-4 inhibitors: An extensive and updated meta-analysis of randomized controlled trials

AIM

Observational studies and metanalyses of randomized trials on Dipeptidyl Peptidase-4 inhibitors (DPP4i) reported discordant results on the risk of pancreatitis and pancreatic cancer with this class of drugs. Aim of the present meta-analysis is the assessment of the effect of DPP4i treatment on the incidence of pancreatitis and pancreatic cancer, collecting all available evidence from randomized controlled trials. Methods Data Sources: an extensive Medline, Embase and Cochrane Database search for sitagliptin or vildagliptin or omarigliptin or saxagliptin or alogliptin or trelagliptin or anagliptin or linagliptin or gemigliptin or evogliptin or teneligliptin was performed up to up to September 30th, 2019. All trials performed on type 2 diabetes, with duration ≥24 weeks, and comparing of DPP4i with placebo or active drugs were collected. The study has been registered on PROSPERO (#153344). Mantel-Haenszel odds ratio (MH-OR) with 95% Confidence Interval (95% CI) was calculated for all outcomes defined above. Results A total of 165 eligible trials were identified. DPP-4 inhibitors were not associated with an increased risk of pancreatitis (MH-OR 1.13 [0.86, 1.47]) or pancreatic cancer (MH-OR 0.86 [0.60, 1.24]) with no significant differences across individual molecules of the class.

CONCLUSIONS

available data do not support the hypothesis of an association of DPP4i treatment with pancreatitis. Present data do not suggest any association of DPP4i with pancreatic cancer, although they are insufficient to draw definitive conclusions.

Long-Term Liraglutide Administration Induces Pancreas Neogenesis in Adult T2DM Mice

In vivo beta-cell neogenesis may be one way to treat diabetes. We aimed to investigate the effect of glucagon-like peptide-1 (GLP-1) on beta-cell neogenesis in type 2 diabetes mellitus (T2DM). Male C57BL/6J mice, 6 wk old, were randomly divided into three groups: Control, T2DM, and T2DM + Lira. T2DM was induced using high-fat diet and intraperitoneal injection of streptozotocin (40 mg/kg/d for 3 d). At 8 wk after streptozotocin injection, T2DM + Lira group was injected intraperitoneally with GLP-1 analog liraglutide (0.8 mg/kg/d) for 4 wk. Apparently for the first time, we report the appearance of a primitive bud connected to pancreas in all adult mice from each group. The primitive bud was characterized by scattered single monohormonal cells expressing insulin, GLP-1, somatostatin, or pancreatic polypeptide, and four-hormonal cells, but no acinar cells and ductal epithelial cells. Monohormonal cells in it were small, newborn, immature cells that rapidly proliferated and expressed cell markers indicative of immaturity. In parallel, Ngn3+ endocrine progenitors and Nestin+ cells existed in the primitive bud. Liraglutide facilitated neogenesis and rapid growth of acinar cells, pancreatic ducts, and blood vessels in the primitive bud. Meanwhile, scattered hormonal cells aggregated into cell clusters and grew into larger islets; polyhormonal cells differentiated into monohormonal cells. Extensive growth of exocrine and endocrine glands resulted in the neogenesis of immature pancreatic lobes in adult mice of T2DM + Lira group. Contrary to predominant acinar cells in mature pancreatic lobes, there were still a substantial number of mesenchymal cells around acinar cells in immature pancreatic lobes, which resulted in the loose appearance. Our results suggest that adult mice preserve the capacity of pancreatic neogenesis from the primitive bud, which liraglutide facilitates in adult T2DM mice. To our knowledge, this is the first time such a phenomenon has been reported.

The Biological Impacts of Sitagliptin on the Pancreas of a Rat Model of Type 2 Diabetes Mellitus: Drug Interactions with Metformin

Sitagliptin, a dipeptidyl peptidase-4 (DPP-4) inhibitor, is a beneficial class of antidiabetic drugs. However, a major debate about the risk of developing pancreatitis is still existing. The aim of the work was to study the histological and immunohistochemical effects of sitagliptin on both endocrine and exocrine pancreases in a rat model of type 2 diabetes mellitus and to correlate these effects with the biochemical findings. Moreover, a possible synergistic effect of sitagliptin, in combination with metformin, was also evaluated. Fifty adult male rats were used and assigned into five equal groups. Group 1 served as control. Group 2 comprised of untreated diabetic rats. Group 3 diabetic rats received sitagliptin. Group 4 diabetic rats received metformin. Group 5 diabetic rats received both combined. Treatments were given for 4 weeks after the induction of diabetes. Blood samples were collected for biochemical assay before the sacrification of rats. Pancreases were removed, weighed, and were processed for histological and immunohistochemical examination. In the untreated diabetic group, the islets appeared shrunken with disturbed architecture and abnormal immunohistochemical reactions for insulin, caspase-3, and inducible nitric oxide synthase (iNOS). The biochemical findings were also disturbed. Morphometrically, there was a significant decrease in the islet size and islet number. Treatment with sitagliptin, metformin, and their combination showed an improvement, with the best response in the combined approach. No evidence of pancreatic injury was identified in the sitagliptin-treated groups. In conclusion, sitagliptin had a cytoprotective effect on beta-cell damage. Furthermore, the data didn't indicate any detrimental effects of sitagliptin on the exocrine pancreas.

Inventing Liraglutide, a Glucagon-Like Peptide-1 Analogue, for the Treatment of Diabetes and Obesity

Glucagon-like peptide-1 (GLP-1) has been in focus since the early 1980s as a long looked for incretin hormone, released from the gastrointestinal tract and with an important effect on glucose-dependent insulin secretion, providing efficient glucose lowering, with little risk for hypoglycemia. The enzyme dipeptidyl peptidase-4 (DPP-4) degrades GLP-1 very fast, and the remaining metabolite is cleared rapidly by the kidneys. Liraglutide is a fatty acid acylated analogue of GLP-1 that provides efficacy for 24 h/day. The mechanism of action for liraglutide is reviewed in detail with focus on pancreatic efficacy and safety, thyroid safety, and weight loss mechanism. Evolving science hypothesizes that GLP-1 has important effects on atherosclerosis, relevant for the cardiovascular benefit seen in the treatment of diabetes and obesity. Also, GLP-1 may be relevant in neurodegenerative diseases.

Pancreatitis Incidence in the Exenatide BID, Exenatide QW, and Exenatide QW Suspension Development Programs: Pooled Analysis of 35 Clinical Trials

INTRODUCTION

Glucagon-like peptide-1 receptor agonists (GLP-1RAs) are widely used for treatment of type 2 diabetes mellitus; however, there have been concerns that GLP-1RA treatment may be associated with an increased incidence of pancreatitis. This study aimed to evaluate the incidence of pancreatitis in a pooled population of type 2 diabetes trials from the clinical development program of the GLP-1RA exenatide as well as to describe patient-level data for all reported cases.

METHODS

The primary analysis examined pooled data among patients with type 2 diabetes from the controlled arms of 35 trials (ranging from 4 to 234 weeks' duration) in the integrated clinical databases for exenatide twice daily, once weekly, and once-weekly suspension, excluding comparator arms with other incretin-based therapies. The exposure-adjusted incidence rate (EAIR) of pancreatitis was calculated for exenatide and non-exenatide (non-incretin-based therapy or placebo) treatment groups. Patient-level data were described for all pancreatitis incidences.

RESULTS

The primary analysis included 5596 patients who received exenatide and 4462 in the non-exenatide group. The mean duration of study medication exposure for the exenatide and non-exenatide treatment groups was 57.0 and 47.9 weeks, respectively. Pancreatitis was diagnosed in 14 patients (exenatide, n = 8; non-exenatide, n = 6), of whom 13 recovered with or without sequelae. The pancreatitis EAIR was 0.1195 events per 100 patient-years [95% confidence interval (CI), 0.0516-0.2154] in the exenatide group versus 0.1276 events per 100 patient-years (95% CI 0.0468-0.2482) in the non-exenatide treatment group. The EAIR ratio for the exenatide versus non-exenatide treatment group was 0.761 (95% CI 0.231-2.510).

CONCLUSION

In this pooled analysis of 10,058 patients among studies comparing exenatide with other glucose-lowering medications or placebo, pancreatitis was rare. The EAIRs of pancreatitis were low and similar between exenatide and non-exenatide treatment groups. No evidence of an association between exenatide and pancreatitis was observed.

FUNDING

Bristol-Myers Squibb and AstraZeneca. Plain language summary available for this article.

Fighting Type-2 Diabetes: Present and Future Perspectives

BACKGROUND

Type-2 diabetes mellitus accounts for 80-90% of diabetic patients. So far, the treatment of diabetes mainly aims at elevating insulin level and lowering glucose level in the peripheral blood and mitigating insulin resistance. Physiologically, insulin secretion from pancreatic β cells is delicately regulated. Thus, how insulin-related therapies could titrate blood glucose appropriately and avoid the occurrence of hypoglycemia remains an important issue for decades. Similar question is addressed on how to attenuate vascular complication in diabetic subjects.

METHODS

We overviewed the evolution of each class of anti-diabetic drugs that have been used in clinical practice, focusing on their mechanisms, clinical results and cautions.

RESULTS

Glucagon-like peptide-1 receptor agonists stimulate β cells for insulin secretion in response to diet but not in fasting stage, which make them superior than conventional insulinsecretion stimulators. DPP-4 inhibitors suppress glucagon-like peptide-1 degradation. Sodium/ glucose co-transporter 2 inhibitors enhance glucose clearance through urine excretion. The appearance of these new drugs provides new information about glycemic control. We update the clinical findings of Glucagon-like peptide-1 receptor agonists, DPP-4 inhibitors and Sodium/glucose cotransporter 2 inhibitors in glycemic control and the risk or progression of cardiovascular disease in diabetic patients. Stem cell therapy might be an alternative tool for diabetic patients to improve β cell regeneration and peripheral ischemia. We summarize the clinical results of mesenchymal stem cells transplanted into patients with diabetic limb and foot.

CONCLUSION

A stepwise intensification of dual and triple therapy for individual diabetic patient is required to achieve therapeutic target.

Case Reports of Pre-clinical Replication Studies in Metabolism and Diabetes

Recent articles have highlighted the lack of reproducibility of data from scientific publications. Here we would argue that a better way to describe and also tackle this matter is to use the term "lack of robustness," since it points toward potential solutions. Presenting several case reports, we highlight examples with common underlying issues from Novo Nordisk's experience: animal model variability, reagent quality, and inter-lab variability. We discuss means to prevent these issues and argue for increased collaborative work and transparent manuscript revision procedures. Collectively, we believe these measures will help promote a more rapid and efficient self-corrective process in diabetes drug target research.

Does the use of incretin-based medications increase the risk of cancer in patients with type-2 diabetes mellitus?

PURPOSE

Incretin-based medications are a novel class of agents for the treatment of type-2 diabetes mellitus (DM2). The safety profile of these medications is not firmly established, and concerns have been raised about their potential carcinogenicity. The objective of our study was to produce new evidence on the effect of incretin-based medications on cancer risk in patients with DM2.

METHODS

We conducted a "retrospective cohort" study with data from the Clinical Practice Research Datalink and the Hospital Episodes Statistics in the UK. New users of either an incretin-based medication (n = 18 885) or a sulfonylurea medication (n = 36 929) between 2007 and 2013 were identified and followed for up to 8 years. Cox proportional-hazards models were used to estimate the quasi-intention-to-treat and quasi-per-protocol hazard-ratios for the association between incretin-based medications with cancer while adjusting for potential confounders.

RESULTS

The adjusted hazard ratio (95% confidence interval) for use of incretin-based medications versus use of sulfonylurea medications for the overall-cancer outcome was 0.97 (0.90, 1.05) in the quasi-intention-to-treat analysis and 0.90 (0.81, 1.00) in the quasi-per-protocol analysis. In both analyses, the hazard-ratio functions over the 8-year follow-up seemed fairly constant, and the 8-year cumulative-risk functions in the two subcohorts were similar.

CONCLUSIONS

Our study suggests that the use of incretin-based medications in patients with DM2 does not increase the risk of cancer relative to the use of sulfonylurea medications, at least in the first several years of the use. Further research is needed to assess long-term effects of the use of incretin-based medications on cancer risk.

Risk of Malignant Neoplasia with Glucagon-Like Peptide-1 Receptor Agonist Treatment in Patients with Type 2 Diabetes: A Meta-Analysis

BACKGROUND

Glucagon-like peptide-1 (GLP-1) receptor agonists are effective glucose-lowering drugs, but there is concern that they may increase the risk of malignant neoplasia. The present meta-analysis examined the safety of GLP-1 receptor agonists with regard to malignant neoplasia.

METHODS

We analyzed data from randomized controlled trials with a minimum duration of 24 weeks that assessed the incidence of neoplasms in type 2 diabetes patients receiving GLP-1 receptor agonists compared with placebo or other hypoglycemic drugs. We searched the MEDLINE, Embase, and Cochrane databases with a language restriction of English through October 1, 2018, and carried out a meta-analysis of the available trial data using a fixed effects model to calculate odds ratios (ORs) for neoplasia.

RESULTS

Thirty-four relevant articles, providing data for 50452 patients, were included in the meta-analysis. Compared with the incidence of malignant neoplasia with placebo or other interventions, no increase in malignant neoplasm formation was observed with the use of GLP-1 receptor agonists (OR 1.04, 95% confidence interval (CI) 0.94-1.15; p = 0.46), liraglutide (OR 1.08, 95% CI 0.91-1.27; p = 0.38), exenatide (OR 1.00, 95% CI 0.86-1.16; p = 1.00), semaglutide (OR 0.89, 95% CI 0.35-2.22; p = 0.80), or albiglutide (OR 1.07, 95% CI 0.23-4.88; p = 0.93). A subanalysis of trials lasting longer than 3 years also showed no increase in the neoplasia risk with GLP-1 receptor agonist use (OR 1.03, 95% CI 0.92-1.15; p = 0.60). Between-trial statistical heterogeneity was low for all comparisons.

CONCLUSION

GLP-1 receptor agonists can be used without safety concerns related to malignant neoplasia in patients with type 2 diabetes.

Oral Semaglutide In The Management Of Type 2 Diabetes: A Report On The Evidence To Date

In recent years, newer drug classes for the treatment of type 2 diabetes mellitus have been released with significant effects on glucose lowering and weight reduction. One of the most promising classes in achieving these goals has been the glucagon-like peptide (GLP)-1 agonists. However, a difficulty with the use of these agents is the need for subcutaneous injections, which can be inconvenient to individuals living with type 2 diabetes. More recently, a GLP-1 agonist has been developed, semaglutide, that can be administered orally which has at least similar effects to the subcutaneous preparation from which this compound is derived. In this review article, we discuss the glycemic and cardiovascular effects of the GLP-1 agonists with special emphasis on oral semaglutide and the potential role of this therapy in individuals with type 2 diabetes.

In the setting of β-cell stress, the pancreatic duct gland transcriptome shows characteristics of an activated regenerative response

The pancreatic duct gland (PDG) compartment has been proposed as a potential stem cell niche based on its coiled tubular structure embedded in mesenchyme, its proliferation and expansion in response to pancreatic injury, and the fact that it contains endocrine and exocrine epithelial cells. Little is known of the molecular signature of the PDG compartment in either a quiescent state or the potentially activated state during β-cell stress characteristic of diabetes. To address this, we performed RNA sequencing on RNA obtained from PDGs of wild-type vs. prediabetic HIP rats, a model of type 2 diabetes. The transcriptome of the PDG compartment, compared with a library of 84 tissue types, placed PDGs midpoint between the exocrine and endocrine pancreas and closely related to seminiferous tubules, consistent with a role as a stem cell niche for the exocrine and endocrine pancreas. Standard differential expression analysis (permissive threshold P < 0.005) identified 245 genes differentially expressed in PDGs from HIP rats vs. WT rats, with overrepresentation of transcripts involved in acute inflammatory responses, regulation of cell proliferation, and tissue development, while pathway analysis pointed to enrichment of cell movement-related pathways. In conclusion, the transcriptome of the PDG compartment is consistent with a pancreatic stem cell niche that is activated by ongoing β-cell stress signals. The documented PDG transcriptome provides potential candidates to be exploited for lineage tracing studies of this as yet little investigated compartment. NEW & NOTEWORTHY The pancreatic duct gland (PDG) compartment has been proposed as a potential stem cell niche. Transcriptome analysis of the PDG gland placed it midpoint between exocrine and endocrine tissues with adaptation toward response to inflammation and increased cell movement in a model of type 2 diabetes with ongoing β-cell apoptosis. These findings support the proposal that PDGs may act as a pancreatic stem cell niche.

Long-term treatment with acylated analogues of apelin-13 amide ameliorates diabetes and improves lipid profile of high-fat fed mice

Previous studies have shown that modified apelin analogues exhibited enzyme resistance in plasma and improved circulating half-life compared to apelin-13. This study investigated the antidiabetic effects of chronic administration of stable long acting fatty acid modified apelin analogues, namely, (Lys8GluPAL)apelin-13 amide and pGlu(Lys8GluPAL)apelin-13 amide, in high-fat fed obese-diabetic mice. Male NIH Swiss mice (groups n = 8) were maintained either on a high-fat diet (45% fat) from 8 to 28 weeks old, or control mice were fed a normal diet (10% fat). When diet induced obesity-diabetes was established after high-fat feeding, mice were injected i.p. once daily with apelin analogues, liraglutide (25 nmol/kg) or saline (controls). Administration of (Lys8GluPAL)apelin-13 amide and pGlu(Lys8GluPAL)apelin-13 amide for 28 days significantly reduced food intake and decreased body weight. Non-fasting glucose was reduced (p<0.01 to p<0.001) and plasma insulin concentrations increased (p<0.01 to p<0.001). This was accompanied by enhanced insulin responses (p<0.01 to p<0.001) and significant reductions in glucose excursion after oral (p<0.01) or i.p. (p<0.01) glucose challenges and feeding. Apelin analogues also significantly improved HbA1c (p<0.01), enhanced insulin sensitivity (p<0.01), reduced triglycerides (p<0.001), increased HDL-cholesterol (p<0.01) and decreased LDL-cholesterol (p<0.01), compared to high-fat fed saline treated control mice. Cholesterol levels were decreased (p<0.01) by pGlu(Lys8GluPAL)apelin-13 amide and both apelin treated groups showed improved bone mineral content, reduced fat deposits and increased plasma GLP-1. Daily treatment with liraglutide mirrored many of these changes (not on bone or adipose tissue), but unlike apelin analogues increased plasma amylase. Consumption of O2, production of CO2, respiratory exchange ratio and energy expenditure were improved by apelin analogues. These results indicate that long-term treatment with acylated analogues (Lys8GluPAL)apelin-13 amide and particularly pGlu(Lys8GluPAL)apelin-13 amide resulted in similar or enhanced therapeutic responses to liraglutide in high-fat fed mice. Fatty acid derived apelin analogues represent a new and exciting development in the treatment of obesity-diabetes.

Synergistic anti-tumor effects of liraglutide with metformin on pancreatic cancer cells

Either metformin or liraglutide has been reported to have anti-tumor effects on pancreatic cancer cells. However, it is not clear whether their combined treatment has additive or synergistic anti-tumor effects on pancreatic cancer cells. In this study, the human pancreatic cancer cell line MiaPaca-2 was incubated with liraglutide and/or metformin. The cell Counting Kit-8 (CCK-8), colony formation, flow cytometry, and wound-healing and transwell migration assays were used to detect cell viability, clonogenic survival, cell cycle and cell migration, respectively. RT-PCR and western blot analyses were used to determine the mRNA and protein levels of related molecules. Results showed that combination treatment with liraglutide (100 nmol/L) and metformin (0.75 mmol/L) significantly decreased cell viability and colony formation, caused cell cycle arrest, upregulated the level of pro-apoptotic proteins Bax and cleaved caspase-3, and inhibited cell migration in the cells, although their single treatment did not exhibit such effects. Combination index value for cell viability indicated a synergistic interaction of liraglutide and metformin. Moreover, the combined treatment with liraglutide and metformin could activate the phosphorylation of AMP-activated protein kinase (AMPK) more potently than their single treatment in the cells. These results suggest that liraglutide in combination with metformin has a synergistic anti-tumor effect on the pancreatic cancer cells, which may be at least partly due to activation of AMPK signaling. Our study provides new insights into the treatment of patients with type 2 diabetes and pancreatic cancer.

Battle of GLP-1 delivery technologies

Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) belong to an important therapeutic class for treatment of type 2 diabetes. Six GLP-1 RAs, each utilizing a unique drug delivery strategy, are now approved by the Food and Drug Administration (FDA) and additional, novel GLP-1 RAs are still under development, making for a crowded marketplace and fierce competition among the manufacturers of these products. As rapid elimination is a major challenge for clinical application of GLP-1 RAs, various half-life extension strategies have been successfully employed including sequential modification, attachment of fatty-acid to peptide, fusion with human serum albumin, fusion with the fragment crystallizable (Fc) region of a monoclonal antibody, sustained drug delivery systems, and PEGylation. In this review, we discuss the scientific rationale of the various half-life extension strategies used for GLP-1 RA development. By analyzing and comparing different approved GLP-1 RAs and those in development, we focus on assessing how half-life extending strategies impact the pharmacokinetics, pharmacodynamics, safety, patient usability and ultimately, the commercial success of GLP-1 RA products. We also anticipate future GLP-1 RA development trends. Since similar drug delivery strategies are also applied for developing other therapeutic peptides, we expect this case study of GLP-1 RAs will provide generalizable concepts for the rational design of therapeutic peptides products with extended duration of action.

Incretin-based therapies and risk of pancreatic cancer in patients with type 2 diabetes: A meta-analysis of randomized controlled trials

AIMS

To perform a meta-analysis of randomized controlled trials (RCTs), including 6 recently published large-scale cardiovascular outcome trials (CVOTs), to evaluate the risk of pancreatic cancer with incretin-based therapies in patients with type 2 diabetes (T2DM).

MATERIALS AND METHODS

For the period January 1, 2007 to May 1, 2017, the PubMed, Embase, Cochrane Central Register and ClininalTrials.gov databases were searched for RCTs in people with T2DM that compared incretin drugs with placebo or other antidiabetic drugs, with treatment and follow-up durations of ≥52 weeks. Two reviewers screened the studies, extracted the data and assessed the risk of bias independently and in duplicate.

RESULTS

A total of 33 studies (n = 79 971), including the 6 CVOTs, with 87 pancreatic cancer events were identified. Overall, the pancreatic cancer risk was not increased in patients administered incretin drugs compared with controls (Peto odds ratio [OR] 0.67, 95% confidence interval [CI] 0.44-1.02). In the 6 CVOTs, 79 pancreatic cancer events were identified in 55 248 participants. Pooled estimates of the 6 CVOTs showed an identical tendency (Peto OR 0.65, 95% CI 0.42-1.01). Notably, in the subgroup of participants who received treatment and follow-up for ≥104 weeks, 84 pancreatic cancer events were identified in 59 919 participants, and a lower risk of pancreatic cancer was associated with incretin-based therapies (Peto OR 0.62, 95% CI 0.41-0.95).

CONCLUSIONS

Treatment with incretin drugs was not associated with an increased risk of pancreatic cancer in people with T2DM. Instead, it might protect against pancreatic malignancy in patients treated for ≥104 weeks.