Therapeutic targets to reduce cardiovascular disease in type 2 diabetes

Molecular imaging of diabetes and diabetic complications: Beyond pancreatic β-cell targeting

Diabetes is a chronic non-communicable disease affecting over 400 million people worldwide. Diabetic patients are at a high risk of various complications, such as cardiovascular, renal, and other diseases. The pathogenesis of diabetes (both type 1 and type 2 diabetes) is associated with a functional impairment of pancreatic β-cells. Consequently, most efforts to manage and prevent diabetes have focused on preserving β-cells and their function. Advances in imaging techniques, such as magnetic resonance imaging, magnetic resonance spectroscopy, positron emission tomography, and single-photon-emission computed tomography, have enabled noninvasive and quantitative detection and characterization of the population and function of β-cells in vivo. These advantages aid in defining and monitoring the progress of diabetes and determining the efficacy of anti-diabetic therapies. Beyond β-cell targeting, molecular imaging of biomarkers associated with the development of diabetes, e.g., lymphocyte infiltration, insulitis, and metabolic changes, may also be a promising strategy for early detection of diabetes, monitoring its progression, and occurrence of complications, as well as facilitating exploration of new therapeutic interventions. Moreover, molecular imaging of glucose uptake, production and excretion in specified tissues is critical for understanding the pathogenesis of diabetes. In the current review, we summarize and discuss recent advances in noninvasive imaging technologies for imaging of biomarkers beyond β-cells for early diagnosis of diabetes, investigation of glucose metabolism, and precise diagnosis and monitoring of diabetic complications for better management of diabetic patients.

Association of Dietary Flavonoid Intake with Prevalence of Type 2 Diabetes Mellitus and Cardiovascular Disease Risk Factors in Korean Women Aged ≥30 Years

The purpose of this study was to investigate the association between dietary flavonoid intake and the prevalence of type 2 diabetes mellitus (T2DM) and cardiovascular disease (CVD) risk factors among Korean women aged ≥30 y. This study used data collected from the 2007-2012 Korean National Health and Nutrition Examination Survey. We excluded subjects who had energy intake <500 kcal or ≥5,000 kcal, were diagnosed with chronic disease, were taking medication, or were pregnant or lactating. The final subjects included 7,963 women, and they were divided into 2 groups, the normal fasting glucose (NFG) group (n=7,738) and the T2DM group (n=225). The intake of flavonoids was estimated on the basis of the flavonoid database. After adjustment for confounding factors, the mean intakes of fruits, anthocyanidins, and flavones were significantly lower in the T2DM group than in the NFG group. In multiple regression analysis, the dietary flavone intake was negatively associated with systolic blood pressure, triglyceride, TG/HDL-cholesterol, and homesostatic model assessment of insulin resistance. Daily intake of flavones above the 25th percentile was associated with a lower prevalence of T2DM compared with intake below the 25th percentile (OR=0.593, 95% confidence interval (CI): 0.414-0.847). These study results showed that dietary flavone intake may have some beneficial effects in reducing CVD risks and prevalence of T2DM in Korean women.

Dose-related antihyperglycemic and hypolipidemic effects of two novel thiazolidin-4-ones in a rodent model of metabolic syndrome

BACKGROUND

The replacement of the thiazolidinedione moiety with a thiazolidinone may yield antidiabetic compounds with similar pleiotropic effects. Hence, the aim of the present study was to explore the dose-related antihyperglycemic and hypolipidemic effects of two synthesized novel thiazolidin-4-one derivatives, one with a nicotinamide and the other with a p-chlorophenoxyacetamide substitution at the N3 position of the thiazolidinone ring (NAT1 and PAT1, respectively), in a rodent model of metabolic syndrome (MetS).

METHODS

Metabolic syndrome was induced in Wistar rats by neonatal administration of monosodium glutamate (i.p.) on 4 consecutive days followed by high-sucrose diet feeding for 6 months. The effects of NAT1 (33 and 66 mg/kg) and molar equivalent doses of PAT1 (40 and 80 mg/kg) on relevant biochemical parameters were evaluated. Because MetS is a state of chronic low-grade inflammation, we also evaluated the effects of these compounds on proinflammatory markers, namely interleukin (IL)-6, tumor necrosis factor (TNF)-α, reactive oxygen species (ROS), and nitric oxide (NO).

RESULTS

Both NAT1 and PAT1 attenuated hyperglycemia, hypertriglyceridemia, hypoalphalipoproteinemia, and glucose intolerance. PAT1 exhibited superior antihyperglycemic and antihypoalphalipoproteinemic effects than NAT1. However, NAT1 had a better triglyceride-lowering effect. At the lower dose tested, both compounds significantly reduced elevated malondialdehyde levels. In addition, PAT1 (80 mg/kg) restored hepatic superoxide dismutase enzyme levels. There was a tendency for NAT1 and PAT1 to inhibit elevated hepatic IL-6 and TNF-α levels, but the differences did not reach statistical significance. In addition, PAT1 exhibited in vitro anti-inflammatory activity by reducing proinflammatory ROS and NO levels in RAW264.7 macrophages.

CONCLUSIONS

The novel thiazolidin-4-ones NAT1 and PAT1 could be potential pleiotropic drug candidates targeting MetS.

Damaging effects of hyperglycemia on cardiovascular function: spotlight on glucose metabolic pathways

The incidence of cardiovascular complications associated with hyperglycemia is a growing global health problem. This review discusses the link between hyperglycemia and cardiovascular diseases onset, focusing on the role of recently emerging downstream mediators, namely, oxidative stress and glucose metabolic pathway perturbations. The role of hyperglycemia-mediated activation of nonoxidative glucose pathways (NOGPs) [i.e., the polyol pathway, hexosamine biosynthetic pathway, advanced glycation end products (AGEs), and protein kinase C] in this process is extensively reviewed. The proposal is made that there is a unique interplay between NOGPs and a downstream convergence of detrimental effects that especially affect cardiac endothelial cells, thereby contributing to contractile dysfunction. In this process the AGE pathway emerges as a crucial mediator of hyperglycemia-mediated detrimental effects. In addition, a vicious metabolic cycle is established whereby hyperglycemia-induced NOGPs further fuel their own activation by generating even more oxidative stress, thereby exacerbating damaging effects on cardiac function. Thus NOGP inhibition, and particularly that of the AGE pathway, emerges as a novel therapeutic intervention for the treatment of cardiovascular complications such as acute myocardial infarction in the presence hyperglycemia.

Safety, efficacy and weight effect of two 11β-HSD1 inhibitors in metformin-treated patients with type 2 diabetes

AIMS

We assessed safety and efficacy of two selective 11β-HSD1 inhibitors (RO5093151/RO-151 and RO5027383/RO-838) in this randomized, controlled study in metformin-treated patients with type 2 diabetes.

METHODS

Patients either received placebo (N = 21), RO-151 BID 5 mg (N = 24) or 200 mg (N = 20) or RO-838 QD 50 mg (N = 21) or 200 mg (N = 24) for 28 days. Metabolic assessments comprising of nine-point plasma glucose profiles, oral glucose tolerance tests and determination of metabolic biomarkers including insulin, C-peptide, glucagon, HbA1c and lipids were done at baseline and end of treatment.

RESULTS

Despite the short treatment duration, both RO-151 and RO-838 showed trends for improved HbA1c and consistent reductions in body weight (-0.86 to -1.67 kg) exceeding those observed with placebo (-0.28 kg, p = 0.019 for 200 mg RO-151 vs. placebo). Insulin sensitivity parameters (e.g. HOMA-IR and Matsuda-Index) improved non-significantly with 200 mg RO-151. Lipid parameters did not consistently improve with either compound, but RO-838 led to non-significant increases in triglycerides and VLDL-cholesterol versus placebo. Both compounds were well tolerated and showed inhibitory effects on 11β-HSD1 activity based on urinary corticosteroid excretion. As reported for other 11β-HSD1-inhibitors increased concentrations of ACTH and adrenal androgen precursors were found with RO-151, but not with RO-838.

CONCLUSIONS

Slight metabolic improvements were seen, in particular with RO-151 high dose, however, the observed changes often did not reach statistical significance and were not clearly dose dependent. Studies of longer duration are needed to further investigate potential benefits and risks of these compounds.

ARTERIAL ENDOTHELIAL DYSFUNCTION AND MYOCARDIAL ISCHEMIA IN PATIENTS WITH CARBOHYDRATE METABOLISM DISTURBANCES

Aim.To assess the role of vasomotor dysfunction and impaired flowdependent vasodilatation as a risk factor of silent myocardial ischemia (SMI) in patients with Type 2 diabetes mellitus (DM-2).

Material and methods.The study included 128 patients (66 men and 62 women; mean age 59,3±4,7 years), who underwent Holter ECG monitoring, stress test (Bruce protocol), echocardiography, vascular ultrasound, and brachial artery endothelium-dependent vasodilatation (EDVD) assessment.

Results.Patients with coronary heart disease and DM-2 demonstrated reduced EDVD levels (3,7±1,1%) and highly prevalent SMI (93,3%). There was a correlation between EDVD and the number (r=–0,68; p<0,05) or duration of SMI episodes (r=–0,53; p<0,01).

Conclusion.Patients with DM-2 require the assessment of vasomotor endothelial function in order to predict cardiovascular complications. Coronary artery endothelial dysfunction, which manifests in inadequate vasodilatation in response to increased myocardial demand for oxygen, plays an important role in the ischemia development and progression.

Safety, tolerability, pharmacokinetics, and pharmacodynamics of multiple rising doses of empagliflozin in patients with type 2 diabetes mellitus

INTRODUCTION

This study examined the safety, tolerability, pharmacokinetics, and pharmacodynamics of empagliflozin, a potent and highly selective sodium glucose cotransporter 2 (SGLT2) inhibitor, in patients with type 2 diabetes mellitus (T2DM).

METHODS

A total of 48 patients with T2DM were randomized to receive one of four doses of empagliflozin (2.5, 10, 25, or 100 mg qd) or placebo over 8 days. In every dose group, nine patients received active drug and three received placebo. The primary endpoint was safety and tolerability. Pharmacokinetic and pharmacodynamic parameters were measured as secondary endpoints.

RESULTS

Empagliflozin was rapidly absorbed, reaching peak levels 1.5-3.0 h after dosing and showed a biphasic decline. The mean terminal elimination half-life ranged from 10 to 19 h. Increases in exposure (area under the plasma concentration-time curve [AUC] and maximum concentration of analyte in plasma [C max]) were approximately proportional with dose. Empagliflozin increased the rate and total amount of glucose excreted in urine compared to placebo. After administration of a single dose of empagliflozin, cumulative amounts of glucose excreted in urine over 24 h ranged from 46.3 to 89.8 g, compared with 5.84 g with placebo. Similar results were seen after multiple doses. Fasting plasma glucose levels decreased by 17.2-25.8% with empagliflozin and by 12.7% with placebo. The frequency of adverse events was 33.3-66.7% with empagliflozin and 41.7% with placebo. There were no changes in urine volume or micturition frequency under the controlled study conditions.

CONCLUSION

Overall, pharmacokinetic assessments demonstrated a dose-proportional increase in drug exposure and support once-daily dosing. Elevated urinary glucose excretion was observed with all doses. Multiple once-daily oral doses of empagliflozin (2.5-100 mg) reduced plasma glucose and were well tolerated in patients with T2DM. EudraCT (2007-000654-32).

Network-based approaches in drug discovery and early development

Identification of novel targets is a critical first step in the drug discovery and development process. Most diseases such as cancer, metabolic disorders, and neurological disorders are complex, and their pathogenesis involves multiple genetic and environmental factors. Finding a viable drug target-drug combination with high potential for yielding clinical success within the efficacy-toxicity spectrum is extremely challenging. Many examples are now available in which network-based approaches show potential for the identification of novel targets and for the repositioning of established targets. The objective of this article is to highlight network approaches for identifying novel targets with greater chances of gaining approved drugs with maximal efficacy and minimal side effects. Further enhancement of these approaches may emerge from effectively integrating computational systems biology with pharmacodynamic systems analysis. Coupling genomics, proteomics, and metabolomics databases with systems pharmacology modeling may aid in the development of disease-specific networks that can be further used to build confidence in target identification.

Safety, tolerability, pharmacokinetics and pharmacodynamics following 4 weeks' treatment with empagliflozin once daily in patients with type 2 diabetes

AIM

To investigate the safety, tolerability, pharmacokinetics and pharmacodynamics of empagliflozin in patients with type 2 diabetes following oral administration of 10, 25 or 100 mg doses once daily over 28 days.

METHODS

A total of 78 patients were assigned to empagliflozin 10 mg (n = 16), 25 mg (n = 16) or 100 mg (n = 30) or placebo (n = 16) for 28 days. Assessments included adverse events (AEs) and pharmacokinetic and pharmacodynamic endpoints.

RESULTS

Empagliflozin exposure increased dose-proportionally over the dose range 10-100 mg and showed linear pharmacokinetics with respect to time. Urinary glucose excretion (UGE) increased from baseline to day 1 by 74, 90 and 81 g with empagliflozin 10, 25 and 100 mg, respectively. The increases in UGE were maintained over 28 days with multiple dosing. Virtually no change in UGE was observed in the placebo group. Significant reductions from baseline in mean daily plasma glucose and fasting plasma glucose were observed with empagliflozin compared with placebo. The incidence of AEs was similar in the empagliflozin and placebo groups (50.0, 56.3 and 66.7% with empagliflozin rising doses and 62.5% with placebo). The most frequently reported AEs were pollakiuria (10.3%), nasopharyngitis (9.0%), constipation (9.0%) and headache (7.7%).

CONCLUSIONS

Oral administration of empagliflozin at doses of 10, 25 or 100 mg once daily over 28 days resulted in significant increases in UGE and reductions in blood glucose compared with placebo, and were well tolerated in patients with type 2 diabetes.

The potential of sodium glucose cotransporter 2 (SGLT2) inhibitors to reduce cardiovascular risk in patients with type 2 diabetes (T2DM)

Type 2 diabetes mellitus (T2DM) significantly increases morbidity and mortality from cardiovascular disease (CVD). Treatments for patients with T2DM have the potential to reduce cardiovascular (CV) risk. This review focuses on the potential of a new class of antidiabetic agents, the sodium glucose cotransporter 2 (SGLT2) inhibitors, to reduce CV risk in patients with T2DM through reductions in hyperglycemia, blood pressure (BP), and body weight. The results of clinical trials of SGLT2 inhibitors are summarized and discussed.

The sodium glucose cotransporter 2 inhibitor empagliflozin does not prolong QT interval in a thorough QT (TQT) study

Background

Empagliflozin is a potent, selective sodium glucose cotransporter 2 (SGLT2) inhibitor in development as an oral antidiabetic treatment. This QT interval study assessed potential effects of empagliflozin on ventricular repolarisation and other electrocardiogram (ECG) parameters.

Methods

A randomised, placebo-controlled, single-dose, double-blind, five-period crossover study incorporating a novel double-placebo period design to reduce sample size, while maintaining full statistical power. Treatments: single empagliflozin doses of 25 mg (therapeutic) and 200 mg (supratherapeutic), matching placebo and open-label moxifloxacin 400 mg (positive control). Triplicate 12-lead ECGs of 10 second duration were recorded at baseline and during the first 24 hours after dosing. The primary endpoint was mean change from baseline (MCfB) in the population heart rate-corrected QT interval (QTcN) between 1–4 hours after dosing.

Results

Thirty volunteers (16 male, 14 female, mean [range] age: 34.5 [18–52] years) were randomised. The placebo-corrected MCfB in QTcN 1–4 hours after dosing was 0.6 (90% CI: -0.7, 1.9) ms and -0.2 (-1.4, 0.9) ms for empagliflozin 25 mg and 200 mg, respectively, below the ICH E14 defined threshold of regulatory concern 10 ms. Assay sensitivity was confirmed by a placebo-corrected MCfB in QTcN 2–4 hours post-dose of 12.4 (10.7, 14.1) ms with moxifloxacin 400 mg. Empagliflozin tolerability was good for all volunteers; 23.3% experienced adverse events (AEs) with empagliflozin and 27.6% with placebo. The most frequent AE was nasopharyngitis.

Conclusions/interpretation

Single doses of empagliflozin 25 mg and 200 mg were not associated with QTcN prolongation and were well tolerated in healthy volunteers.

Trial registration

ClinicalTrials.gov: NCT01195675

SAR and Computer-Aided Drug Design Approaches in the Discovery of Peroxisome Proliferator-Activated Receptor γ Activators: A Perspective

Activators of PPARγ, Troglitazone (TGZ), Rosiglitazone (RGZ), and Pioglitazone (PGZ) were introduced for treatment of Type 2 diabetes, but TGZ and RGZ have been withdrawn from the market along with other promising leads due cardiovascular side effects and hepatotoxicity. However, the continuously improving understanding of the structure/function of PPARγ and its interactions with potential ligands maintain the importance of PPARγ as an antidiabetic target. Extensive structure activity relationship (SAR) studies have thus been performed on a variety of structural scaffolds by various research groups. Computer-aided drug discovery (CADD) approaches have also played a vital role in the search and optimization of potential lead compounds. This paper focuses on these approaches adopted for the discovery of PPARγ ligands for the treatment of Type 2 diabetes. Key concepts employed during the discovery phase, classification based on agonistic character, applications of various QSAR, pharmacophore mapping, virtual screening, molecular docking, and molecular dynamics studies are highlighted. Molecular level analysis of the dynamic nature of ligand-receptor interaction is presented for the future design of ligands with better potency and safety profiles. Recently identified mechanism of inhibition of phosphorylation of PPARγ at SER273 by ligands is reviewed as a new strategy to identify novel drug candidates.

Pharmaceutically controlled designer circuit for the treatment of the metabolic syndrome

Synthetic biology has significantly advanced the design of genetic devices that can reprogram cellular activities and provide novel treatment strategies for future gene- and cell-based therapies. However, many metabolic disorders are functionally linked while developing distinct diseases that are difficult to treat using a classic one-drug-one-disease intervention scheme. For example, hypertension, hyperglycemia, obesity, and dyslipidemia are interdependent pathologies that are collectively known as the metabolic syndrome, the prime epidemic of the 21st century. We have designed a unique therapeutic strategy in which the clinically licensed antihypertensive drug guanabenz (Wytensin) activates a synthetic signal cascade that stimulates the secretion of metabolically active peptides GLP-1 and leptin. Therefore, the signal transduction of a chimeric trace-amine-associated receptor 1 (cTAAR1) was functionally rewired via cAMP and cAMP-dependent phosphokinase A (PKA)-mediated activation of the cAMP-response element binding protein (CREB1) to transcription of synthetic promoters containing CREB1-specific cAMP response elements. Based on this designer signaling cascade, it was possible to use guanabenz to dose-dependently control expression of GLP-1-Fc(mIgG)-Leptin, a bifunctional therapeutic peptide hormone that combines the glucagon-like peptide 1 (GLP-1) and leptin via an IgG-Fc linker. In mice developing symptoms of the metabolic syndrome, this three-in-one treatment strategy was able to simultaneously attenuate hypertension and hyperglycemia as well as obesity and dyslipidemia. Using a clinically licensed drug to coordinate expression of therapeutic transgenes combines drug- and gene-based therapies for coordinated treatment of functionally related metabolic disorders.

Renal and cardiac effects of DPP4 inhibitors--from preclinical development to clinical research

Inhibitors of type 4 dipeptidyl peptidase (DDP-4) were developed and approved for the oral treatment of type 2 diabetes. Its mode of action is to inhibit the degradation of incretins, such as type 1 glucagon like peptide (GLP-1), and GIP. GLP-1 stimulates glucose-dependent insulin secretion from pancreatic beta-cells and suppresses glucagon release from alpha-cells, thereby improving glucose control. Besides its action on the pancreas type 1 glucagon like peptide has direct effects on the heart, vessels and kidney mainly via the type 1 glucagon like peptide receptor (GLP-1R). Moreover, there are substrates of DPP-4 beyond incretins that have proven renal and cardiovascular effects such as BNP/ANP, NPY, PYY or SDF-1 alpha. Preclinical evidence suggests that DPP-4 inhibitors may be effective in acute and chronic renal failure as well as in cardiac diseases like myocardial infarction and heart failure. Interestingly, large cardiovascular meta-analyses of combined phase II/III clinical trials with DPP-4 inhibitors point all in the same direction: a potential reduction of cardiovascular events in patients treated with these agents. A pooled analysis of pivotal phase III, placebo-controlled, registration studies of linagliptin further showed a significant reduction of urinary albumin excretion after 24 weeks of treatment. The observation suggests direct renoprotective effects of DPP-4 inhibition that may go beyond its glucose-lowering potential. Type 4 dipeptidyl peptidase inhibitors have been shown to be very well tolerated in general, but for those excreted via the kidney dose adjustments according to renal function are needed to avoid side effects. In conclusion, the direct cardiac and renal effects seen in preclinical studies as well as meta-analysis of clinical trials may offer additional potentials - beyond improvement of glycemic control - for this newer class of drugs, such as acute kidney failure, chronic kidney failure as well as acute myocardial infarction and heart failure.

The landscape of drug discovery in atherosclerosis and dyslipidaemia revisited: an update of patenting activity

INTRODUCTION

This paper is an update of a previous paper I published in Expert Opinion of Therapeutic Patents in 2008. The paper was a survey of patenting activity in the fields of atherosclerosis and dyslipidaemia, which identified trends in patenting by reviewing two major mechanistic categories, metabolic/dyslipidaemia and vascular/inflammation, as well as examining the interest in certain specific targets over a period of 10 years.

METHODS

In this update, the same methodology was followed using the Espacenet of the European Patent Office (EPO) to identify patents claiming therapeutics for atherosclerosis or dyslipidaemia (excluding the wider metabolic syndrome).

EXPERT OPINION

A major change in the field over the past 5 years has been the departure of larger companies from the field. This is reflected in the patenting activity. Patenting has been at a stable rate over the recent years with few new targets being highlighted. It is suggested that, for this field to return to the higher rates of patenting seen over 10 years ago, breakthroughs in translational medicine and in the ability to conduct clinical trials, particularly in biomarkers and imaging, will need to take place.

Ongoing clinical trials evaluating the cardiovascular safety and efficacy of therapeutic approaches to diabetes mellitus

Research has substantiated that patients with type 2 diabetes mellitus are at increased risk for cardiovascular (CV) disease. It is well established that aggressive management of metabolic risk factors is critical to reducing morbidity and mortality in patients with diabetes. A number of clinical trials are currently focusing on evaluating the safety and efficacy of therapeutic approaches to diabetes. These trials will provide additional information on the role of aggressive management of glucose in patients with diabetes and CV risk. This article provides a summary of these ongoing trials, and discusses the impact of glycemic control and strategies to promote CV risk reduction in patients with diabetes.

Drug-target network and polypharmacology studies of a Traditional Chinese Medicine for type II diabetes mellitus

Many Traditional Chinese Medicines (TCMs) are effective to relieve complicated diseases such as type II diabetes mellitus (T2DM). In this work, molecular docking and network analysis were employed to elucidate the action mechanism of a medical composition which had clinical efficacy for T2DM. We found that multiple active compounds contained in this medical composition would target multiple proteins related to T2DM and the biological network would be shifted. We predicted the key players in the medical composition and some of them have been reported in literature. Meanwhile, several compounds such as Rheidin A, Rheidin C, Sennoside C, procyanidin C1 and Dihydrobaicalin were notable although no one have reported their pharmacological activity against T2DM. The association between active compounds, target proteins and other diseases was also discussed.

Research and development of glucokinase activators for diabetes therapy: theoretical and practical aspects

Glucokinase Glucokinase (GK GK ; EC 2.7.1.1.) phosphorylates and regulates glucose metabolism in insulin-producing pancreatic beta-cells, hepatocytes, and certain cells of the endocrine and nervous systems allowing it to play a central role in glucose homeostasis glucose homeostasis . Most importantly, it serves as glucose sensor glucose sensor in pancreatic beta-cells mediating glucose-stimulated insulin biosynthesis and release and it governs the capacity of the liver to convert glucose to glycogen. Activating and inactivating mutations of the glucokinase gene cause autosomal dominant hyperinsulinemic hypoglycemia and hypoinsulinemic hyperglycemia in humans, respectively, illustrating the preeminent role of glucokinase in the regulation of blood glucose and also identifying the enzyme as a potential target for developing antidiabetic drugs antidiabetic drugs . Small molecules called glucokinase activators (GKAs) glucokinase activators (GKAs) which bind to an allosteric activator allosteric activator site of the enzyme have indeed been discovered and hold great promise as new antidiabetic agents. GKAs increase the enzyme's affinity for glucose and also its maximal catalytic rate. Consequently, they stimulate insulin biosynthesis and secretion, enhance hepatic glucose uptake, and augment glucose metabolism and related processes in other glucokinase-expressing cells. Manifestations of these effects, most prominently a lowering of blood glucose, are observed in normal laboratory animals and man but also in animal models of diabetes and patients with type 2 diabetes mellitus (T2DM T2DM ) type 2 diabetes mellitus (T2DM) . These compelling concepts and results sustain a strong R&D effort by many pharmaceutical companies to generate GKAs with characteristics allowing for a novel drug treatment of T2DM.

Insulin and resveratrol act synergistically, preventing cardiac dysfunction in diabetes, but the advantage of resveratrol in diabetics with acute heart attack is antagonized by insulin

Resveratrol (RSV), a natural phenolic compound, has been found to display cardiovascular protective and insulin-sensitizing properties. In this study, the effects of RSV and its combination with insulin on mortality, hemodynamics, insulin signaling, and nitrosative stress were compared in streptozotocin (STZ)-induced diabetic rats with or without acute myocardial ischemia/reperfusion (I/R) injury. Under normoxic conditions, cardiac systolic and diastolic functions and insulin-mediated Akt/GLUT4 (glucose transporter 4) activation were impaired in STZ-diabetic rats. The combination of RSV and insulin significantly prevented the above diabetes-associated abnormalities. Notwithstanding that, the diabetic state rendered the animals more susceptible to myocardial I/R injury, and the mortality rate and inducible nitric oxide synthase (iNOS)/nitrotyrosine protein expression and superoxide anion production were also further increased in I/R-injured diabetic hearts. In contrast, RSV treatment alone resulted in a lower mortality rate (from 62.5 to 18%) and better cardiac systolic function than its combination with insulin. RSV also inhibited iNOS/nitrotyrosine protein overexpression and superoxide anion overproduction in I/R-injured diabetic myocardium. Hyperglycemia, impairment of insulin signaling, overexpression of iNOS/nitrotyrosine, and superoxide anion overproduction were markedly rescued by the combination treatment, which did not show an improvement in mortality rate (30%) or cardiac performance over RSV treatment alone. These results indicate that insulin and RSV synergistically prevented cardiac dysfunction in diabetes and this may be in parallel with activation of the insulin-mediated Akt/GLUT4 signaling pathway. Although activation of the protective signal (Akt/GLUT4) and suppression of the adverse markers (iNOS, nitrotyrosine, and superoxide anion) were simultaneously observed in insulin and RSV combination treatment, insulin counteracted the advantage of RSV in diabetics with acute heart attack.

Effect of dapagliflozin in patients with type 2 diabetes who have inadequate glycaemic control with metformin: a randomised, double-blind, placebo-controlled trial

BACKGROUND

Correction of hyperglycaemia and prevention of glucotoxicity are important objectives in the management of type 2 diabetes. Dapagliflozin, a selective sodium-glucose cotransporter-2 inhibitor, reduces renal glucose reabsorption in an insulin-independent manner. We assessed the efficacy and safety of dapagliflozin in patients who have inadequate glycaemic control with metformin.

METHODS

In this phase 3, multicentre, double-blind, parallel-group, placebo-controlled trial, 546 adults with type 2 diabetes who were receiving daily metformin (>/=1500 mg per day) and had inadequate glycaemic control were randomly assigned to receive one of three doses of dapagliflozin (2.5 mg, n=137; 5 mg, n=137; or 10 mg, n=135) or placebo (n=137) orally once daily. Randomisation was computer generated and stratified by site, implemented with a central, telephone-based interactive voice response system. Patients continued to receive their pre-study metformin dosing. The primary outcome was change from baseline in haemoglobin A(1c)(HbA(1c)) at 24 weeks. All randomised patients who received at least one dose of double-blind study medication and who had both a baseline and at least one post-baseline measurement (last observation carried forward) were included in the analysis. Data were analysed by use of ANCOVA models. This trial is registered with ClinicalTrials.gov, number NCT00528879.

FINDINGS

534 patients were included in analysis of the primary endpoint (dapagliflozin 2.5 mg, n=135; dapagliflozin 5 mg, n=133; dapagliflozin 10 mg, n=132; placebo, n=134). At week 24, mean HbA(1c) had decreased by -0.30% (95% CI -0.44 to -0.16) in the placebo group, compared with -0.67% (-0.81 to -0.53, p=0.0002) in the dapagliflozin 2.5 mg group, -0.70% (-0.85 to -0.56, p<0.0001) in the dapagliflozin 5 mg group, and -0.84% (-0.98 to -0.70, p<0.0001) in the dapagliflozin 10 mg group. Symptoms of hypoglycaemia occurred in similar proportions of patients in the dapagliflozin (2-4%) and placebo groups (3%). Signs, symptoms, and other reports suggestive of genital infections were more frequent in the dapagliflozin groups (2.5 mg, 11 patients [8%]; 5 mg, 18 [13%]; 10 mg, 12 [9%]) than in the placebo group (seven [5%]). 17 patients had serious adverse events (four in each of the dapagliflozin groups and five in the placebo group).

INTERPRETATION

Addition of dapagliflozin to metformin provides a new therapeutic option for treatment of type 2 diabetes in patients who have inadequate glycaemic control with metformin alone.

FUNDING

Bristol-Myers Squibb and AstraZeneca.

XOMA 052, an anti-IL-1{beta} monoclonal antibody, improves glucose control and {beta}-cell function in the diet-induced obesity mouse model

Recent evidence suggests that IL-1beta-mediated glucotoxicity plays a critical role in type 2 diabetes mellitus. Although previous work has shown that inhibiting IL-1beta can lead to improvements in glucose control and beta-cell function, we hypothesized that more efficient targeting of IL-1beta with a novel monoclonal antibody, XOMA 052, would reveal an effect on additional parameters affecting metabolic disease. In the diet-induced obesity model, XOMA 052 was administered to mice fed either normal or high-fat diet (HFD) for up to 19 wk. XOMA 052 was administered as a prophylactic treatment or as a therapy. Mice were analyzed for glucose tolerance, insulin tolerance, insulin secretion, and lipid profile. In addition, the pancreata were analyzed for beta-cell apoptosis, proliferation, and beta-cell mass. Mice on HFD exhibited elevated glucose and glycated hemoglobin levels, impaired glucose tolerance and insulin secretion, and elevated lipid profile, which were prevented by XOMA 052. XOMA 052 also reduced beta-cell apoptosis and increased beta-cell proliferation. XOMA 052 maintained the HFD-induced compensatory increase in beta-cell mass, while also preventing the loss in beta-cell mass seen with extended HFD feeding. Analysis of fasting insulin and glucose levels suggests that XOMA 052 prevented HFD-induced insulin resistance. These studies provide new evidence that targeting IL-1beta in vivo could improve insulin sensitivity and lead to beta-cell sparing. This is in addition to previously reported benefits on glycemic control. Taken together, the data presented suggest that XOMA 052 could be effective for treating many aspects of type 2 diabetes mellitus.

Assessing the cardio-cerebrovascular safety of vildagliptin: meta-analysis of adjudicated events from a large Phase III type 2 diabetes population

AIM

To assess the cardiovascular and cerebrovascular (CCV) safety of the dipeptidyl peptidase-IV inhibitor vildagliptin.

METHODS

Data were pooled from 25 Phase III studies of vildagliptin, used either as monotherapy or combination therapy, with durations of 12 weeks to > or = 2 years. The safety of vildagliptin [50 mg qd (N = 1393) or 50 mg bid (N = 6116)] was assessed relative to a pool of all comparators [both placebo and active comparators (N = 6061)]. CCV events were adjudicated in a prospective, blinded fashion by an independent CCV adjudication committee. Meta-analysis of confirmed CCV events was performed with Mantel-Haenszel risk ratios (RRs); categories included in the composite endpoint were acute coronary syndrome, transient ischaemic attack (with imaging evidence of infarction), stroke and CCV death. Subgroup analyses by age (< and > or = 65 years), gender and cardiovascular (CV) risk status [high CV risk status defined as a previous history of events in the Standard MedDRA Queries of ischaemic heart disease, cardiac failure, ischaemic cerebrovascular conditions and/or embolic/thrombotic events, arterial) were also carried out. In addition, unadjusted and exposure-adjusted incidences are presented for both the composite endpoint and its components.

RESULTS

Relative to all comparators, the RRs for the composite endpoint were < 1 for both vildagliptin 50 mg qd [RR = 0.88; 95% CI (0.37, 2.11)] and vildagliptin 50 mg bid [RR = 0.84; 95% CI (0.62, 1.14)]. The results were consistent across subgroups defined by age, gender and CV risk status, including the higher CV risk subgroups of elderly patients [RR for vildagliptin 50 mg bid vs. all comparators = 1.04; 95% CI (0.62, 1.73)], males [RR = 0.87; 95% CI (0.60, 1.24)] or patients with a high CV risk status [RR = 0.78; 95% CI (0.51, 1.19)]. The exposure-adjusted incidences of each component of the composite endpoint for vildagliptin 50 mg bid were also lower than or similar to those of all comparators.

CONCLUSIONS

In a large meta-analysis, vildagliptin was not associated with an increased risk of adjudicated CCV events relative to all comparators in the broad population of type 2 diabetes including patients at increased risk of CCV events.