Therapeutic Effects of Switching to Anagliptin from Other DPP-4 Inhibitors in T2DM Patients with Inadequate Glycemic Control: A Non-interventional, Single-Arm, Open-Label, Multicenter Observational Study

INTRODUCTION

The effects of switching DPP-4 inhibitors in type 2 diabetes mellitus (T2DM) patients are being widely studied. However, information of which factors affect the therapeutic response is limited. We evaluated the difference in HbA1c lowering effect by comorbidity and other variables after switching to anagliptin in patients with T2DM inadequately controlled by other DPP-4 inhibitors.

METHODS

In a multicenter, open-label, single-arm, prospective observational study, patients with T2DM, HbA1c ≥ 7.0% who have taken DPP-4 inhibitors other than anagliptin, either alone or in combination (DPP-4 inhibitors + metformin/sulfonylurea (SU)/thiazolidinedione (TZD)/insulin), for at least 8 weeks were enrolled. After the switch to anagliptin, HbA1c and available clinical characteristics were determined.

RESULTS

The change in HbA1c levels from baseline to week 12 and 24 was - 0.40% and - 0.42% in all patients. However, comparing the subgroups without and with comorbidities, the change in HbA1c levels at weeks 12 and 24 was - 0.68% and - 0.89% vs. - 0.27% and 0.22%, respectively. In addition, the proportion of patients achieving HbA1c < 7% from baseline to week 12 and 24 was increased to 70% and 70% vs. 20% and 24%, respectively. Duration of T2DM and different subtype classes of DPP-4 inhibitor did not significantly contribute to the change in HbA1c.

CONCLUSION

In patients with T2DM poorly controlled by other DPP-4 inhibitors, HbA1c levels were significantly decreased after switching to anagliptin. Given that the change in HbA1c was greater in patients without comorbidities than in patients with comorbidities, switching to anagliptin before adding other oral hypoglycemic agents (OHAs) may be an option in patients without comorbidities.

Comparison of the Effectiveness of Once-Daily Alogliptin/Metformin and Twice-Daily Anagliptin/Metformin Combination Tablet in a Randomized, Parallel-Group, Open-Label Trial in Japanese Patients with Type 2 Diabetes

INTRODUCTION

The combination tablets of dipeptidyl peptidase-4 (DPP-4) inhibitors and metformin are used for both once-daily and twice-daily agents in Japan. If there is no difference in effectiveness between the once-daily and twice-daily DPP-4 inhibitor/metformin combination tablets, the once-daily agent is advantageous in terms of frequency of administration. The aim of this study was to compare the effectiveness of once-daily alogliptin/metformin combination tablet (alogliptin 25 mg/metformin 500 mg) and twice-daily anagliptin/metformin combination tablet low dose (LD) (anagliptin 100 mg/metformin 250 mg).

METHODS

Forty-eight Japanese patients with type 2 diabetes whose metformin administration of 250 mg twice daily had remained unchanged for at least 8 weeks, except when using DPP-4 inhibitors, glucagon-like peptide-1 receptor agonists, or insulin, were randomized to either the once-daily alogliptin/metformin combination tablet group or the twice-daily anagliptin/metformin combination tablet LD group. The primary endpoint was the difference in glycosylated hemoglobin (HbA1c) levels from baseline to week 12 of administration, whereas the secondary endpoints were fasting blood glucose, body mass index (BMI), and adherence.

RESULTS

Forty-four patients completed the study, and intention-to-treat analyses were performed. The adjusted mean value (standard error) for the change in HbA1c from week 0 to 12, was - 0.75 (0.109)% for the once-daily alogliptin/metformin combination tablet group and - 0.65 (0.109)% for the twice-daily anagliptin/metformin combination tablet LD group, with an intergroup difference of - 0.10% (95% confidence interval, CI - 0.407, 0.215). The upper limit of the bilateral 95% CI was 0.215%, below the 0.40% pre-defined as the non-inferiority margin. Fasting blood glucose, BMI, and adherence were not significantly different between the groups.

CONCLUSIONS

The once-daily alogliptin/metformin combination tablet was non-inferior to the twice-daily anagliptin/metformin combination tablet LD in Japanese patients with type 2 diabetes.

TRIAL REGISTRATION

University Hospital Medical Information Network Clinical Trial Registry (UMIN-CTR) (registration number: UMIN000034951).

Anagliptin prevents lipopolysaccharide (LPS)- induced inflammation and activation of macrophages

Sepsis is a multiple organ dysfunction syndrome (MODS) induced by infection, which significantly threatens public health. The overactivation of inflammatory reactions and oxidative stress participate in the pathogenesis of sepsis. Anagliptin, a novel anti-diabetic agent widely applied for the treatment of type II diabetes, has been recently claimed to possess anti-inflammatory properties. Here, the protective effects of anagliptin on lipopolysaccharide (LPS)- stimulated macrophages will be checked to explore the possible pharmacological property of anagliptin on sepsis. The state of oxidative stress was dramatically activated by LPS, accompanied by the upregulation of toll-like receptor 4 (TLR4) and high mobility group box-1 (HMGB-1), as well as the elevated expression of inducible nitric oxide synthase (iNOS) and production of nitric oxide (NO). After treatment with anagliptin, the state of oxidative stress in macrophages was alleviated, with the downregulation of TLR4, HMGB-1, iNOS, and the declined release of NO. The excessive secretion of inflammatory factors, activation of the NF-κB pathway, and promoted expression level of receptor-interacting protein 1 (RIP1) were observed in LPS- stimulated macrophages, all of which were greatly reversed by the introduction of anagliptin. Lastly, the protective properties of anagliptin on LPS- treated macrophages, including the inhibitory effects on inflammation and the NF-κB pathway, were dramatically abolished by the overexpression of RIP1 in macrophages. Collectively, anagliptin prevented LPS-induced inflammation and activation of P338D1 macrophages by repressing the expression level of RIP1.

Differential Effects of DPP-4 Inhibitors, Anagliptin and Sitagliptin, on PCSK9 Levels in Patients with Type 2 Diabetes Mellitus who are Receiving Statin Therapy

Aim: Proprotein convertase subtilisin/kexin type 9 (PCSK9) degrades the low-density lipoprotein (LDL) receptor, leading to hypercholesterolemia and cardiovascular risk. Treatment with a statin leads to a compensatory increase in circulating PCSK9 level. Anagliptin, a dipeptidyl peptidase-4 (DPP-4) inhibitor, was shown to decrease LDL cholesterol (LDL-C) levels to a greater extent than that by sitagliptin, another DPP-4 inhibitor, in the Randomized Evaluation of Anagliptin versus Sitagliptin On low-density lipoproteiN cholesterol in diabetes (REASON) trial. We investigated PCSK9 concentration in type 2 diabetes mellitus (T2DM) and the impact of treatment with anagliptin or sitagliptin on PCSK9 level as a sub-analysis of the REASON trial.

Methods: PCSK9 concentration was measured at baseline and after 52 weeks of treatment with anagliptin ( n =122) or sitagliptin ( n =128) in patients with T2DM who were receiving statin therapy. All of the included patients had been treated with a DPP-4 inhibitor prior to randomization.

Results: Baseline PCSK9 level was positively, but not significantly, correlated with LDL-C and was independently associated with platelet count and level of triglycerides. Concomitant with reduction of LDL-C, but not hemoglobin A1c (HbA1c), by anagliptin, PCSK9 level was significantly increased by treatment with sitagliptin (218±98 vs. 242±115 ng/mL, P =0.01), but not anagliptin (233±97 vs. 250±106 ng/mL, P =0.07).

Conclusions: PCSK9 level is independently associated with platelet count and level of triglycerides, but not LDL-C, in patients with T2DM. Anagliptin reduces LDL-C level independent of HbA1c control in patients with T2DM who are on statin therapy possibly by suppressing excess statin-mediated PCSK9 induction and subsequent degradation of the LDL receptor.

Anagliptin Monotherapy for Six Months in Patients With Type 2 Diabetes Mellitus and Hyper-Low-Density Lipoprotein Cholesterolemia Reduces Plasma Levels of Fasting Low-Density Lipoprotein Cholesterol and Lathosterol: A Single-Arm Intervention Trial

Background

Anagliptin, a dipeptidyl peptidase-4 (DPP-4) inhibitor, has been shown to decrease plasma low-density lipoprotein cholesterol (LDL-C) levels. The objective of our study was to elucidate the mechanisms responsible for the anagliptin-mediated improvements in high LDL-C levels (hyper-LDL cholesterolemia).

Methods

We prospectively examined the effects of anagliptin monotherapy on fasting plasma lathosterol, sitosterol, and campesterol levels in patients with type 2 diabetes mellitus and hyper-LDL cholesterolemia for 6 months. We examined 14 patients who did not use hypoglycemic or lipid-lowering drugs for 4 months before initiating the study. Plasma variables related to glucose and lipid metabolism were measured before and after 6 months of treatment and pre- and postprandially using the cookie-loading test.

Results

After treatment, anagliptin monotherapy (n = 14) significantly decreased fasting LDL-C (175.6 to 148.5 mg/dL, mean values before and after the treatment, respectively) and plasma lathosterol levels (3.56 to 2.49 mg/dL), whereas it did not lower fasting sitosterol or campesterol levels. Furthermore, fasting plasma lathosterol levels were negatively correlated with preprandial glucagon-like peptide-1 (GLP-1) levels after anagliptin treatment.

Conclusions

Anagliptin monotherapy may have a beneficial effect on lipid metabolism, which could be mediated by the inhibition of hepatic cholesterol synthesis rather than the inhibition of intestinal lipid transport.

Anagliptin prevented interleukin 1β (IL-1β)-induced cellular senescence in vascular smooth muscle cells through increasing the expression of sirtuin1 (SIRT1)

Vascular smooth muscle cell senescence plays a pivotal role in the pathogenesis of atherosclerosis. Anagliptin is a novel dipeptidyl peptidase-4 (DPP-4) inhibitor for the treatment of hyperglycemia. Recent progress indicates that DPP-4 inhibitors show a wide range of cardiovascular benefits. We hypothesize that Anagliptin plays a role in vascular smooth muscle cell senescence and this may imply its modulation of atherosclerosis. Here, the beneficial effect of Anagliptin against interleukin 1β (IL-1β)-induced cell senescence in vascular smooth muscle cells was studied to learn the promising therapeutic capacity of Anagliptin on atherosclerosis. Firstly, we found that Anagliptin treatment ameliorated the elevated secretions of tumor necrosis factor-α (TNF-α), interleukin 6 (IL-6), and macrophage chemoattractant protein-1 (MCP-1). Secondly, our findings indicate that exposure to IL-1β reduced telomerase activity from 26.7 IU/L to 15.8 IU/L, which was increased to 20.3 and 24.6 IU/L by 2.5 and 5 μM Anagliptin, respectively. In contrast, IL-1β stimulation increased senescence- associated β-galactosidase (SA-β-gal) staining to 3.1- fold compared to the control group, it was then reduced to 2.3- and 1.6- fold by Anagliptin dose-dependently. Thirdly, Anagliptin dramatically reversed the upregulated p16, p21, and downregulated sirtuin1 (SIRT1) in IL-1β-treated vascular smooth muscle cells. Lastly, the protective effect of Anagliptin against cellular senescence in vascular smooth muscle cells was abolished by silencing of SIRT1. In conclusion, Anagliptin protects vascular smooth muscle cells from cytokine-induced senescence, and the action of Anagliptin in vascular smooth muscle cells requires SIRT1 expression.

Stromal cell-derived factor 1 (SDF1) attenuates platelet-derived growth factor-B (PDGF-B)-induced vascular remodeling for adipose tissue expansion in obesity

Platelet-derived growth factor-B (PDGF-B) is a main factor to promote adipose tissue angiogenesis, which is responsible for the tissue expansion in obesity. In this process, PDGF-B induces the dissociation of pericytes from blood vessels; however, its regulatory mechanism remains unclear. In the present study, we found that stromal cell-derived factor 1 (SDF1) plays an essential role in this regulatory mechanism. SDF1 mRNA was increased in epididymal white adipose tissue (eWAT) of obese mice. Ex vivo pharmacological analyses using cultured adipose tissue demonstrated that physiological concentrations (1-100 pg/mL) of SDF1 inhibited the PDGF-B-induced pericyte dissociation from vessels via two cognate SDF1 receptors, CXCR4 and CXCR7. In contrast, higher concentrations (> 1 ng/mL) of SDF1 alone caused the dissociation of pericytes via CXCR4, and this effect disappeared in the cultured tissues from PDGF receptor β (PDGFRβ) knockout mice. To investigate the role of SDF1 in angiogenesis in vivo, the effects of anagliptin, an inhibitor of dipeptidyl peptidase 4 (DPP4) that degrades SDF1, were examined in mice fed a high-fat diet. Anagliptin increased the SDF1 levels in the serum and eWAT. These changes were associated with a reduction of pericyte dissociation and fat accumulation in eWAT. AMD3100, a CXCR4 antagonist, cancelled these anagliptin effects. In flow-cytometry analysis, anagliptin increased and decreased the PDGF-B expression in endothelial cells and macrophages, respectively, whereas anagliptin reduced the PDGFRβ expression in pericytes of eWAT. These results suggest that SDF1 negatively regulates the adipose tissue angiogenesis in obesity by altering the reactivity of pericytes to PDGF-B.

Anagliptin stimulates osteoblastic cell differentiation and mineralization

Osteoporosis is a common debilitating bone disease characterized by loss of bone mass and degradation of the bone architecture, which is primarily driven by dysregulated differentiation of mesenchymal stem cells into bone-producing osteoblasts. Osteoblasts contribute to bone formation by secreting various proteins that guide the deposition of bone extracellular matrix, such as alkaline phosphatase (ALP), osteocalcin (OCN), and osteopontin (OPN). The Wnt/β-catenin pathway is widely recognized as a regulator of bone mass and is required to maintain bone homeostasis. Hormones have long been recognized as playing a key role in bone metabolism, and in recent years, growing evidence has shown that diabetes is a risk factor for osteoporosis. In the present study, we investigated the effects of the antidiabetic drug anagliptin on the differentiation and mineralization of osteoblasts induced by osteogenic medium. Anagliptin promotes insulin production via inhibition of dipeptidyl peptidase IV (DPP-4), an enzyme that targets the incretin hormone glucagon-like peptide 1 (GLP-1) for degradation. Our findings show that anagliptin significantly increases the differentiation of MSCs into osteoblasts via activation of RUNX2. Anagliptin significantly increased matrix deposition and mineralization by osteoblasts, as evidenced by elevated levels of ALP, OCN, OPN, and BMP-2. We further demonstrate that anagliptin activates the canonical and noncannonical Wnt signaling pathways and that silencing of Wnt/β-catenin signaling completely abolished the effects of anagliptin. Thus, anagliptin might be a safe, effective therapy for type II diabetes that might show promise as a therapy against osteoporosis.

Treatment with anagliptin, a DPP-4 inhibitor, decreases FABP4 concentration in patients with type 2 diabetes mellitus at a high risk for cardiovascular disease who are receiving statin therapy

Background

Fatty acid-binding protein 4 (FABP4) acts as a novel adipokine, and elevated FABP4 concentration is associated with obesity, insulin resistance and atherosclerosis. Dipeptidyl peptidase-4 (DPP-4) inhibitors, a class of antidiabetic drugs, have distinct structures among the drugs, possibly leading to a drug class effect and each drug effect. Sitagliptin, a DPP-4 inhibitor, has been reported to decrease FABP4 concentration in drug-naïve and sulfonylurea-treated patients with type 2 diabetes mellitus. Anagliptin, another DPP-4 inhibitor, was shown to decrease low-density lipoprotein cholesterol (LDL-C) level to a greater extent than that by sitagliptin in the Randomized Evaluation of Anagliptin vs. Sitagliptin On low-density lipoproteiN cholesterol in diabetes (REASON) trial.

Aim and methods

As a sub-analysis study using data obtained from the REASON trial, we investigated the effects of treatment with anagliptin (n = 148, male/female: 89/59) and treatment with sitagliptin (n = 159, male/female: 93/66) for 52 weeks on FABP4 concentration in patients with type 2 diabetes mellitus at a high risk for cardiovascular events who were receiving statin therapy.

Results

The DPP-4 inhibitor had been administered in 82% of the patients in the anagliptin group and 81% of the patients in sitagliptin group prior to randomization. Serum FABP4 level was significantly decreased by 7.9% by treatment with anagliptin (P = 0.049) and was not significantly decreased by treatment with sitagliptin (P = 0.660). Change in FABP4 level was independently associated with basal FABP4 level and changes in waist circumference and creatinine after adjustment of age, sex and the treatment group.

Conclusion

Anagliptin decreases serum FABP4 concentration independent of change in hemoglobin A1c or LDL-C in patients with type 2 diabetes mellitus and dyslipidemia who are on statin therapy.

Trial registration ClinicalTrials.gov number NCT02330406. Registered January 5, 2015, https://clinicaltrials.gov/ct2/show/NCT02330406

Anagliptin suppresses diet-induced obesity through enhancing leptin sensitivity and ameliorating hyperphagia in high-fat high-sucrose diet fed mice

Obesity is a major risk factors for type 2 diabetes, and weight loss is beneficial to diabetic patients who are obese or overweight. Dipeptidyl peptidase-4 (DPP-4) inhibitors are anti-diabetic drugs. Although it has been known that the effect of most of the DPP-4 inhibitors on body weight is neutral, several studies suggested that some DPP-4 inhibitors suppressed body weight. Nonetheless, the mechanisms underlying DPP-4 inhibitor-induced weight loss are not fully understood. In this study, the mice fed high-fat high sucrose diet (HFHSD) containing a DPP4 inhibitor, anagliptin, showed reduced food intake and body weight compared to the mice fed non-treated HFHSD, but oxygen consumption and respiratory exchange ratio (RER) were not altered. Sequential administration of leptin suppressed food intake and body weight more apparently in anagliptin treated HFHSD fed mice than non-treated HFHSD fed mice. Oxygen consumption and RER were comparable between anagliptin treated and non-treated mice after leptin administration. The number of phospho STAT3 expressed cells in the arcuate nucleus after leptin administration was increased in anagliptin treated mice compared to non-treated mice. These data suggested that anagliptin ameliorated leptin resistance induced by HFHSD and thereby decreased food intake and body weight. These effects of anagliptin could be beneficial to the treatment of obese diabetic patients.

Comparison of Lipid-Lowering Effects of Anagliptin and Miglitol in Patients With Type 2 Diabetes: A Randomized Trial

Background

Recently, we reported that the level of lathosterol, a cholesterol synthesis marker, was suppressed after 1 month of treatment with anagliptin, a dipeptidyl peptidase-4 inhibitor. In this study, we administered either anagliptin or miglitol, an alpha-glucosidase inhibitor, for 3 months in patients with type 2 diabetes and compared the lipid-lowering effects of anagliptin with those of miglitol.

Methods

This study was a 12-week, open-label, prospective, randomized, parallel-group comparison trial. Fifty-two patients with type 2 diabetes who aged 20 - 70 years with a low-density lipoprotein cholesterol (LDL-C) level of over 120 mg/dL, and with no history of treatment with antihyperlipidemic drugs were enrolled. Patients were randomly assigned to either the anagliptin group or miglitol group. The 100 mg of anagliptin was administered twice a day for the anagliptin group and 50 mg of miglitol was administered thrice a day for miglitol group. The changes in lipids, cholesterol synthesis, and absorption markers were evaluated after 12 weeks.

Results

Fifty-two participants were initially enrolled in the trial, and 47 of them completed the protocol. There was no significant difference in LDL-C, cholesterol synthesis, and the absorption markers between anagliptin and miglitol groups.

Conclusions

Anagliptin and miglitol are similarly effective on lipid and glycemic control.

Differences in lipid metabolism between anagliptin and sitagliptin in patients with type 2 diabetes on statin therapy: a secondary analysis of the REASON trial

Background

Anagliptin, a dipeptidyl peptidase-4 inhibitor, is reported to reduce the level of low-density lipoprotein cholesterol (LDL-C). The underlying mechanism of this effect and effect on lipid metabolism however remains uncertain.

Aim and methods

We therefore evaluate the effects of anagliptin on lipid metabolism-related markers compared with those of sitagliptin. The study was a secondary analysis using data obtained from the Randomized Evaluation of Anagliptin versus Sitagliptin On low-density lipoproteiN cholesterol in diabetes (REASON) trial. This trial in patients with type 2 diabetes at a high risk of cardiovascular events and on statin therapy showed that anagliptin reduced LDL-C levels to a greater extent than sitagliptin. Cholesterol absorption (campesterol and sitosterol) and synthesis (lathosterol) markers were measured at baseline and 52 weeks in the study cohort (n = 353).

Results

There was no significant difference in the changes of campesterol or sitosterol between the two treatment groups (p = 0.85 and 0.55, respectively). Lathosterol concentration was increased significantly at 52 weeks with sitagliptin treatment (baseline, 1.2 ± 0.7 μg/mL vs. 52 weeks, 1.4 ± 1.0 μg/mL, p = 0.02), whereas it did not change in the anagliptin group (baseline, 1.3 ± 0.8 μg/mL vs. 52 weeks, 1.3 ± 0.7 μg/mL, p = 0.99). The difference in absolute change between the two groups showed a borderline significance (p = 0.06).

Conclusion

These findings suggest that anagliptin reduces LDL-C level by suppressing excess cholesterol synthesis, even in combination with statin therapy.

Trial registration ClinicalTrials.gov number NCT02330406. https://clinicaltrials.gov/ct2/show/NCT02330406; registered January 5, 2015.

Drug interactions of dipeptidyl peptidase 4 inhibitors involving CYP enzymes and P-gp efflux pump

Dipeptidyl peptidase 4 (DPP4) inhibitors are oral antidiabetic drugs approved to manage type 2 diabetes mellitus. Saxagliptin is a substrate of CYP3A4/5 enzymes while other DPP4 inhibitors such as sitagliptin, linagliptin, gemigliptin and teneligliptin are weak substrates of CYP3A4. DPP4 inhibitors have also been identified as substrates of P-gp. Hence, the drugs inhibiting or inducing CYP3A4/5 enzymes and/or P-gp can alter the pharmacokinetics of DPP4 inhibitors. This review is aimed to identify the drugs interacting with DPP4 inhibitors. The plasma concentrations of saxagliptin have been reported to be increased significantly by the concomitant administration of ketoconazole or diltiazem while no significant interactions between various DPP4 inhibitors and drugs like warfarin, digoxin or cyclosporine have been identified.

Efficacy of anagliptin as compared to linagliptin on metabolic parameters over 2 years of drug consumption: A retrospective cohort study

AIM

To evaluate the comparative effectiveness of anagliptin and linagliptin on the clinical parameters in patients with type 2 diabetes mellitus (T2DM).

METHODS

A 2-year retrospective cohort study was conducted in patients with T2DM who received anagliptin and linagliptin. We enrolled 234 patients (anagliptin group, 117 patients; linagliptin group, 117 patients).

RESULTS

The glycemic control considerably improved 3, 6, 12, and 24 mo after the administration of both dipeptidyl peptidase-4 (DPP-4) inhibitors. Following the administration of anagliptin, the diastolic blood pressure and serum total cholesterol levels decreased. However, serum high-density lipoprotein cholesterol levels increased and urinary albumin-creatinine ratio decreased following linagliptin administration. Furthermore, the liver function improved after the administration of linagliptin.

CONCLUSION

These findings suggest that that the efficacy of DPP-4 inhibitors on the blood pressure, lipid profile, and liver function differs between anagliptin and linagliptin.

LC/QTOF/MS/MS characterization, molecular docking and in silico toxicity prediction studies on degradation products of anagliptin

Pharmaceutical drugs are potential molecules with specific biological activity. However, long-term use of these chemical molecules can affect the human physiological system because of their increased levels in the human body. Therefore, identification and structure elucidation of impurities or degradation products should be taken into consideration in order to assure drug safety. The present study assessed the degradation behaviour of dipeptidyl peptidase-4 (DPP-4) inhibitor anagliptin under different stress conditions as per ICH guidelines Q1A (R2) followed by elucidation of the structure of degradation products. All the stress samples were analysed by using UPLC/PDA. The superior separation of drug from its degradation products was attained with time programmed gradient elution on BEH C18 (100 mm × 2.1 mm, 1.7 μm) column using 10 mM ammonium formate (aqueous) and acetonitrile (organic) as the mobile phase components. All the degradation products of anagliptin were characterized using LC/QTOF/MS/MS. In addition, the activity and toxicity of degradation products were determined through molecular docking and in silico toxicity prediction studies, respectively. The developed UPLC/PDA method was validated as per ICH guidelines in terms of specificity, accuracy, precision, linearity and robustness.

Effect of Anagliptin on Glycemic and Lipid Profile in Patients With Type 2 Diabetes Mellitus

Background

Anagliptin is a dipeptidyl peptidase-4 (DPP-4) inhibitor expected to improve the lipid profile as well as glycemic control. However, findings from large-scale prospective trials have not been obtained.

Methods

We performed a multicenter prospective trial in patients with type 2 diabetes receiving anagliptin to evaluate its effect on glycemic control and the lipid profile. A total of 95 patients received anagliptin at 200 mg twice daily. Markers of glucose and lipid metabolism were measured at baseline and after 12 and 24 weeks of administration, and the absolute changes and percent changes were determined.

Results

Both HbA1c and plasma glucose were significantly decreased by anagliptin therapy. Regarding the lipid profile, total cholesterol (TC) showed a significant decrease at 12 weeks, while TC, low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C) were significantly decreased at 24 weeks. Multivariate analysis revealed that female sex was an independent predictor of greater reduction of TC, LDL-C, and HDL-C, while a baseline TC level ≥ 200 mg/dL predicted greater reduction of TC and a baseline HDL-C level ≥ 40 mg/dL predicted greater reduction of LDL-C and HDL-C.

Conclusions

This study suggested that anagliptin significantly reduced TC, LDL-C, and HDL-C levels, as well as improving glycemic control, particularly in female patients.

Mechanism of lipid-lowering action of the dipeptidyl peptidase-4 inhibitor, anagliptin, in low-density lipoprotein receptor-deficient mice

Aims/Introduction

Dipeptidyl peptidase‐4 inhibitors are used for treatment of patients with type 2 diabetes. In addition to glycemic control, these agents showed beneficial effects on lipid metabolism in clinical trials. However, the mechanism underlying the lipid‐lowering effect of dipeptidyl peptidase‐4 inhibitors remains unclear. Here, we investigated the lipid‐lowering efficacy of anagliptin in a hyperlipidemic animal model, and examined the mechanism of action.

Materials and Methods

Male low‐density lipoprotein receptor‐deficient mice were administered 0.3% anagliptin in their diet. Plasma lipid levels were assayed and lipoprotein profile was analyzed using high‐performance liquid chromatography. Hepatic gene expression was examined by deoxyribonucleic acid microarray and quantitative polymerase chain reaction analyses. Sterol regulatory element‐binding protein transactivation assay was carried out in vitro.

Results

Anagliptin treatment significantly decreased the plasma total cholesterol (14% reduction, P < 0.01) and triglyceride levels (27% reduction, P < 0.01). Both low‐density lipoprotein cholesterol and very low‐density lipoprotein cholesterol were also decreased significantly by anagliptin treatment. Sterol regulatory element‐binding protein‐2 messenger ribonucleic acid expression level was significantly decreased at night in anagliptin‐treated mice (15% reduction, P < 0.05). Anagliptin significantly suppressed sterol regulatory element‐binding protein activity in HepG2 cells (21% decrease, P < 0.001).

Conclusions

The results presented here showed that the dipeptidyl peptidase‐4 inhibitor, anagliptin, exhibited a lipid‐lowering effect in a hyperlipidemic animal model, and suggested that the downregulation of hepatic lipid synthesis was involved in the effect. Anagliptin might have beneficial effects on lipid metabolism in addition to a glucose‐lowering effect.

High-fat diet feeding significantly attenuates anagliptin-induced regeneration of islets of Langerhans in streptozotocin-induced diabetic mice

BACKGROUND

DPP-4 inhibitors reportedly exert effects on both alpha and beta cells, and promote the proliferation and survival of beta cells. We investigated the effects of anagliptin on structurally-impaired islets of Langerhans in streptozotocin (STZ)-treated mice, fed either a normal or a high-fat diet. Pdx-1 expression in the pancreas and serum insulin/glucagon concentrations were also examined.

FINDINGS

Anagliptin treatment significantly up-regulated pancreatic Pdx-1 expression, with elevated serum glucagon-like peptide-1 concentrations, regardless of whether the diet was normal or high-fat. However, interestingly, the beta cell regeneration, structural normalization of islets of Langerhans including alpha cell: beta cell area ratios, and serum insulin elevation, all observed with anagliptin administration in the animals fed a normal diet, were markedly suppressed in the high-fat fed group.

CONCLUSIONS

High-fat diet feeding clearly weakened the regenerative effects of anagliptin on the islets of Langerhans in STZ-treated mice. Our findings suggest the importance of normalizing lipid metabolism for full manifestation of DPP-4 inhibitor effects on the islets of Langerhans.