Effects of Combining Linagliptin Treatment with BI-38335, A Novel SGLT2 Inhibitor, on Pancreatic Islet Function and Inflammation in db/db Mice

Dipeptidyl peptidase-4 (DPP-4) inhibitors enhance incretin actions and beta-cell function. Concurrently, sodium-glucose co-transporter 2 (SGLT2) inhibitors block renal glucose reabsorption promoting excretion. In this study, we investigated the effects of linagliptin (a DPP-4 inhibitor) and BI-38335 (an SGLT2 inhibitor), individually and in combination, on glucose homeostasis, islet function, and pancreatic islet morphology in db/db mice. Diabetic and non-diabetic mice received linagliptin (3 mg/kg), BI-38335 (1 mg/kg), the two drugs in combination or control once daily for 8 weeks. Blood glucose homeostasis and insulin sensitivity were assessed. Pancreatic islet function and morphology as well as inflammatory factors and toll like receptor 2 (TLR2) pathways involved in islet inflammation were investigated. Active treatments markedly reduced blood glucose and glycated hemoglobin A1c (HbA1c) levels, with the combined treatment showing the greater effects. Insulin resistance was improved in the BI-38335 and combination groups with the enhancement of insulin sensitivity and significant increase of serum adiponectin levels. The combined treatment exhibited greater effects on enhanced islet glucose-stimulated insulin secretion and improved glucose tolerance. Moreover, the combination restored the islet beta-/alpha-cell ratio, reduced beta-cell apoptosis, decreased expression of islet immune cell markers, and suppressed factors related to the TLR2 pathway. In addition, all active treatments reduced serum lipid profiles, though the combination produced more robust effects. Collectively, our data show that combined treatment with BI-38335 and linagliptin work, at least in part, synergistically to benefit islet cell function/architecture and insulin resistance, thus improving glycemic control.     

Linagliptin improves insulin sensitivity and hepatic steatosis in diet-induced obesity

Linagliptin (TRADJENTA?) is a selective dipeptidyl peptidase-4 (DPP-4) inhibitor. DPP-4 inhibition attenuates insulin resistance and improves peripheral glucose utilization in humans. However, the effects of chronic DPP-4 inhibition on insulin sensitivity are not known. The effects of long-term treatment (3-4 weeks) with 3 mg/kg/day or 30 mg/kg/day linagliptin on insulin sensitivity and liver fat content were determined in diet-induced obese C57BL/6 mice. Chow-fed animals served as controls. DPP-4 activity was significantly inhibited (67-89%) by linagliptin (P<0.001). Following an oral glucose tolerance test, blood glucose concentrations (measured as area under the curve) were significantly suppressed after treatment with 3 mg/kg/day (-16.5% to -20.3%; P<0.01) or 30 mg/kg/day (-14.5% to -26.4%; P<0.05) linagliptin (both P<0.01). Liver fat content was significantly reduced by linagliptin in a dose-dependent manner (both doses P<0.001). Diet-induced obese mice treated for 4 weeks with 3 mg/kg/day or 30 mg/kg/day linagliptin had significantly improved glycated hemoglobin compared with vehicle (both P<0.001). Significant dose-dependent improvements in glucose disposal rates were observed during the steady state of the euglycemic-hyperinsulinemic clamp: 27.3 mg/kg/minute and 32.2 mg/kg/minute in the 3 mg/kg/day and 30 mg/kg/day linagliptin groups, respectively; compared with 20.9 mg/kg/minute with vehicle (P<0.001). Hepatic glucose production was significantly suppressed during the clamp: 4.7 mg/kg/minute and 2.1 mg/kg/minute in the 3 mg/kg/day and 30 mg/kg/day linagliptin groups, respectively; compared with 12.5 mg/kg/minute with vehicle (P<0.001). In addition, 30 mg/kg/day linagliptin treatment resulted in a significantly reduced number of macrophages infiltrating adipose tissue (P<0.05). Linagliptin treatment also decreased liver expression of PTP1B, SOCS3, SREBP1c, SCD-1 and FAS (P<0.05). Other tissues like muscle, heart and kidney were not significantly affected by the insulin sensitizing effect of linagliptin. Long-term linagliptin treatment reduced liver fat content in animals with diet-induced hepatic steatosis and insulin resistance, and may account for improved insulin sensitivity.     

The Dipeptidyl Peptidase-4 Inhibitor Linagliptin Preserves Endothelial Function in Mesenteric Arteries from Type 1 Diabetic Rats without Decreasing Plasma Glucose

The aim of the study was to investigate the effect of the DPP-4 inhibitor linagliptin on the mechanism(s) of endothelium-dependent relaxation in mesenteric arteries from STZ-induced diabetic rats. Both normal and diabetic animals received linagliptin (2 mg/kg) daily by oral gavage for a period of 4 weeks. To measure superoxide generation in mesenteric arteries, lucigenin-enhanced chemiluminescence was used. ACh-induced relaxation of mesenteric arteries was assessed using organ bath techniques and Western blotting was used to investigate protein expression. Pharmacological tools (1μM TRAM-34, 1μM apamin, 100 nM Ibtx, 100 μM L-NNA, 10 μM ODQ) were used to distinguish between NO and EDH-mediated relaxation. Linagliptin did not affect plasma glucose, but did decrease vascular superoxide levels. Diabetes reduced responses to ACh but did not affect endothelium-independent responses to SNP. Linagliptin improved endothelial function indicated by a significant increase in responses to ACh. Diabetes impaired the contribution of both nitric oxide (NO) and endothelium-dependent hyperpolarization (EDH) to endothelium-dependent relaxation and linagliptin treatment significantly enhanced the contribution of both relaxing factors. Western blotting demonstrated that diabetes also increased expression of Nox2 and decreased expression and dimerization of endothelial NO synthase, effects that were reversed by linagliptin. These findings demonstrate treatment of type 1 diabetic rats with linagliptin significantly reduced vascular superoxide levels and preserved both NO and EDH-mediated relaxation indicating that linagliptin can improve endothelial function in diabetes independently of any glucose lowering activity.     

The Effects of Empagliflozin,an SGLT2 Inhibitor,on Pancreatic β-Cell Mass and Glucose Homeostasis in Type 1 Diabetes

The novel sodium glucose co-transporter 2 (SGLT2) inhibitor empagliflozin has recently been reported to improve glycemic control in streptozotocin-induced type 1 diabetic rats in an insulin-independent manner, via an increase in urinary glucose output. We investigated the potential of empagliflozin to recover insulin pathways in type 1 diabetes by improving pancreatic β-cell mass. Blood glucose homeostasis was assessed by an intraperitoneal glucose tolerance test. Serum insulin levels and insulin mRNA expression were determined using commercial insulin ELISA kits and real-time quantitative polymerase chain reaction, respectively. Immunohistochemistry was used to investigate β-cell areas, β-cell proliferation, apoptosis of pancreatic β-cells, and reactive oxygen species production in the pancreatic β-cells. Results showed that glucose tolerance was significantly improved in streptozotocin-induced type 1 diabetic mice treated with empagliflozin. Empagliflozin-treated mice also showed an increase in insulin mRNA expression. Higher serum insulin levels were detected in mice treated with empagliflozin compared with the vehicle group. Immunohistochemistry indicated that β-cell area/total pancreatic area and the expression of cell proliferation marker Ki-67 (co-stained with insulin) were significantly enhanced by empagliflozin treatment. These effects were due, probably, to a reduction in apoptosis and reactive oxygen species in the pancreatic β-cells. Taken together, the results of this study indicate that empagliflozin may have a beneficial effect on preserving β-cell regeneration, thus improving blood glucose homeostasis in type 1 diabetes mellitus, probably via the protection of pancreatic β-cell from glucotoxicity-induced oxidative stress.     

The Sodium-Glucose Co-Transporter 2 Inhibitor Empagliflozin Improves Diabetes-Induced Vascular Dysfunction in the Streptozotocin Diabetes Rat Model by Interfering with Oxidative Stress and Glucotoxicity

Objective

In diabetes, vascular dysfunction is characterized by impaired endothelial function due to increased oxidative stress. Empagliflozin, as a selective sodium-glucose co-transporter 2 inhibitor (SGLT2i), offers a novel approach for the treatment of type 2 diabetes by enhancing urinary glucose excretion. The aim of the present study was to test whether treatment with empagliflozin improves endothelial dysfunction in type I diabetic rats via reduction of glucotoxicity and associated vascular oxidative stress.

Methods

Type I diabetes in Wistar rats was induced by an intravenous injection of streptozotocin (60 mg/kg). One week after injection empagliflozin (10 and 30 mg/kg/d) was administered via drinking water for 7 weeks. Vascular function was assessed by isometric tension recording, oxidative stress parameters by chemiluminescence and fluorescence techniques, protein expression by Western blot, mRNA expression by RT-PCR, and islet function by insulin ELISA in serum and immunohistochemical staining of pancreatic tissue. Advanced glycation end products (AGE) signaling was assessed by dot blot analysis and mRNA expression of the AGE-receptor (RAGE).

Results

Treatment with empagliflozin reduced blood glucose levels, normalized endothelial function (aortic rings) and reduced oxidative stress in aortic vessels (dihydroethidium staining) and in blood (phorbol ester/zymosan A-stimulated chemiluminescence) of diabetic rats. Additionally, the pro-inflammatory phenotype and glucotoxicity (AGE/RAGE signaling) in diabetic animals was reversed by SGLT2i therapy.

Conclusions

Empagliflozin improves hyperglycemia and prevents the development of endothelial dysfunction, reduces oxidative stress and improves the metabolic situation in type 1 diabetic rats. These preclinical observations illustrate the therapeutic potential of this new class of antidiabetic drugs.     

Effects of SGLT2 Inhibition in Human Kidney Proximal Tubular Cells—Renoprotection in Diabetic Nephropathy?

Sodium/glucose cotransporter 2 (SGLT2) inhibitors are oral hypoglycemic agents used to treat patients with diabetes mellitus. SGLT2 inhibitors block reabsorption of filtered glucose by inhibiting SGLT2, the primary glucose transporter in the proximal tubular cell (PTC), leading to glycosuria and lowering of serum glucose. We examined the renoprotective effects of the SGLT2 inhibitor empagliflozin to determine whether blocking glucose entry into the kidney PTCs reduced the inflammatory and fibrotic responses of the cell to high glucose. We used an in vitro model of human PTCs. HK2 cells (human kidney PTC line) were exposed to control 5 mM, high glucose (HG) 30 mM or the profibrotic cytokine transforming growth factor beta (TGFβ1; 0.5 ng/ml) in the presence and absence of empagliflozin for up to 72 h. SGLT1 and 2 expression and various inflammatory/fibrotic markers were assessed. A chromatin immunoprecipitation assay was used to determine the binding of phosphorylated smad3 to the promoter region of the SGLT2 gene. Our data showed that TGFβ1 but not HG increased SGLT2 expression and this occurred via phosphorylated smad3. HG induced expression of Toll-like receptor-4, increased nuclear deoxyribonucleic acid binding for nuclear factor kappa B (NF-κB) and activator protein 1, induced collagen IV expression as well as interleukin-6 secretion all of which were attenuated with empagliflozin. Empagliflozin did not reduce high mobility group box protein 1 induced NF-κB suggesting that its effect is specifically related to a reduction in glycotoxicity. SGLT1 and GLUT2 expression was not significantly altered with HG or empagliflozin. In conclusion, empagliflozin reduces HG induced inflammatory and fibrotic markers by blocking glucose transport and did not induce a compensatory increase in SGLT1/GLUT2 expression. Although HG itself does not regulate SGLT2 expression in our model, TGFβ increases SGLT2 expression through phosphorylated smad3.     

Empagliflozin improves left ventricular diastolic function of db/db mice

ObjectivesInvestigation of the effect of SGLT2 inhibition by empagliflozin on left ventricular function in a model of diabetic cardiomyopathy.BackgroundSGLT2 inhibition is a new strategy to treat diabetes. In the EMPA-REG Outcome trial empagliflozin treatment reduced cardiovascular and overall mortality in patients with diabetes presumably due to beneficial cardiac effects, leading to reduced heart failure hospitalization. The relevant mechanisms remain currently elusive but might be mediated by a shift in cardiac substrate utilization leading to improved energetic supply to the heart.MethodsWe used db/db mice on high-fat western diet with or without empagliflozin treatment as a model of severe diabetes. Left ventricular function was assessed by pressure catheter with or without dobutamine stress.ResultsTreatment with empagliflozin significantly increased glycosuria, improved glucose metabolism, ameliorated left ventricular diastolic function and reduced mortality of mice. This was associated with reduced cardiac glucose concentrations and decreased calcium/calmodulin-dependent protein kinase (CaMKII) activation with subsequent less phosphorylation of the ryanodine receptor (RyR). No change of cardiac ketone bodies or branched-chain amino acid (BCAA) metabolites in serum was detected nor was cardiac expression of relevant catabolic enzymes for these substrates affected.ConclusionsIn a murine model of severe diabetes empagliflozin-dependent SGLT2 inhibition improved diastolic function and reduced mortality. Improvement of diastolic function was likely mediated by reduced spontaneous diastolic sarcoplasmic reticulum (SR) calcium release but independent of changes in cardiac ketone and BCAA metabolism.     

Dapagliflozin,SGLT2 Inhibitor,Attenuates Renal Ischemia-Reperfusion Injury

Dapagliflozin, a new type of drug used to treat diabetes mellitus (DM), is a sodium/glucose cotransporter 2 (SGLT2) inhibitor. Although some studies showed that SGLT2 inhibition attenuated reactive oxygen generation in diabetic kidney the role of SGLT2 inhibition is unknown. We evaluated whether SLT2 inhibition has renoprotective effects in ischemia-reperfusion (IR) models. We evaluated whether dapagliflozin reduces renal damage in IR mice model. In addition, hypoxic HK2 cells were treated with or without SGLT2 inhibitor to investigate cell survival, the apoptosis signal pathway, and the induction of hypoxia-inducible factor 1 (HIF1) and associated proteins. Dapagliflozin improved renal function. Dapagliflozin reduced renal expression of Bax, renal tubule injury and TUNEL-positive cells and increased renal expression of HIF1 in IR-injured mice. HIF1 inhibition by albendazole negated the renoprotective effects of dapagliflozin treatment in IR-injured mice. In vitro, dapagliflozin increased the expression of HIF1, AMP-activated protein kinase (AMPK), and ERK and increased cell survival of hypoxic HK2 cells in a dose-dependent manner. In conclusion, dapagliflozin attenuates renal IR injury. HIF1 induction by dapagliflozin may play a role in renoprotection against renal IR injury.     

A DPP-4 Inhibitor Suppresses Fibrosis and Inflammation on Experimental Autoimmune Myocarditis in Mice

Myocarditis is a critical inflammatory disorder which causes life-threatening conditions. No specific or effective treatment has been established. DPP-4 inhibitors have salutary effects not only on type 2 diabetes but also on certain cardiovascular diseases. However, the role of a DPP-4 inhibitor on myocarditis has not been investigated. To clarify the effects of a DPP-4 inhibitor on myocarditis, we used an experimental autoimmune myocarditis (EAM) model in Balb/c mice. EAM mice were assigned to the following groups: EAM mice group treated with a DPP-4 inhibitor (linagliptin) (n = 19) and those untreated (n = 22). Pathological analysis revealed that the myocardial fibrosis area ratio in the treated group was significantly lower than in the untreated group. RT-PCR analysis demonstrated that the levels of mRNA expression of IL-2, TNF-α, IL-1β and IL-6 were significantly lower in the treated group than in the untreated group. Lymphocyte proliferation assay showed that treatment with the DPP-4 inhibitor had no effect on antigen-induced spleen cell proliferation. Administration of the DPP-4 inhibitor remarkably suppressed cardiac fibrosis and reduced inflammatory cytokine gene expression in EAM mice. Thus, the agents present in DPP-4 inhibitors may be useful to treat and/or prevent clinical myocarditis.     

The Emerging Role Of Adjunctive Noninsulin Antihyperglycemic Therapy In The Management Of Type 1 Diabetes

Objective: Review available data on adjunctive therapies for type 1 diabetes (T1D), with a special focus on newer antihyperglycemic agents.Methods: Published data on hypoglycemia, obesity, mortality, and goal attainment in T1D were reviewed to determine unmet therapeutic needs. PubMed databases and abstracts from recent diabetes meetings were searched using the term “type 1 diabetes” and the available and investigational sodium-glucose cotransporter (SGLT) inhibitors, glucagon-like peptide 1 (GLP-1) receptor agonists, dipeptidyl peptidase 4 inhibitors, and metformin.Results: The majority of patients with T1D do not meet glycated hemoglobin (A1C) goals established by major diabetes organizations. Hypoglycemia risks and a rising incidence of obesity and metabolic syndrome featured in the T1D population limit optimal use of intensive insulin therapy. Noninsulin antihyperglycemic agents may enable T1D patients to achieve target A1C levels using lower insulin doses, which may reduce the risk of hypoglycemia. In pilot studies, the SGLT2 inhibitor dapagliflozin and the GLP-1 receptor agonist liraglutide reduced blood glucose, weight, and insulin dose in patients with T1D. Phase 2 studies with the SGLT2 inhibitor empagliflozin and the dual SGLT1 and SGLT2 inhibitor sotagliflozin, which acts in the gut and the kidney, have demonstrated reductions in A1C, weight, and glucose variability without an increased incidence of hypoglycemia.Conclusion: Newer antihyperglycemic agents, particularly GLP-1 agonists, SGLT2 inhibitors, and dual SGLT1 and SGLT2 inhibitors, show promise as adjunctive treatment for T1D that may help patients achieve better glucose control without weight gain or increased hypoglycemia.Abbreviations:A1C = glycated hemoglobinBMI = body mass indexCI = confidence intervalDKA = diabetic ketoacidosisDPP-4 = dipeptidyl peptidase 4GLP-1 = glucagonlike peptide 1PYY = polypeptide tyrosine tyrosineSGLT = sodium-glucose cotransporterSGLT1 = sodium-glucose cotransporter 1SGLT2 = sodium-glucose cotransporter 2T1D = type 1 diabetesT2D = type 2 diabetesTDD = total daily dosage     

Discovery of triazole-based uracil derivatives bearing amide moieties as novel dipeptidyl peptidase-IV inhibitors

Dipeptidyl peptidase-IV (DPP-4) is a validated target for T2DM treatment. We previously reported a novel series of triazole-based uracil derivatives bearing aliphatic carboxylic acids with potent DPP-4 inhibitory activities in vitro, but these compounds showed poor hypoglycemic effects in vivo. Herein we further optimized the triazole moiety by amidation of the carboxylic acid to improve in vivo activities. Two series of compounds 3a-f and 4a-g were designed and synthesized. By screening in DPP-4, compound 4c was identified as a potent DPP-4 inhibitor with the IC₅₀ value of 28.62 nM. Docking study revealed compound 4c has a favorable binding mode and interpreted the SAR of these analogs. DPP-8 and DPP-9 tests indicated compound 4c had excellent selectivity over DPP-8 and DPP-9. Further in vivo evaluations revealed that compound 4c showed more potent hypoglycemic activity than its corresponding carboxylic acid in ICR mice and dose-dependently reduced glucose levels in type 2 diabetic C57BL/6 mice. The overall results have shown that compound 4c could be a promising lead for further development of novel DPP-4 agents treating T2DM.     

MK-626, a dipeptidyl peptidase-4 inhibitor, does not improve the hyperglycemia or hyperinsulinemia of nonobese diabetic MKR mice

Dipeptidyl peptidase-4 (DPP-4) inhibitors increase circulating levels of incretin hormones, which can enhance insulin secretion and β cell function. The aim of this study was to evaluate the effectiveness of MK-626 (a novel DPP-4 inhibitor) to reduce the hyperglycemia and hyperinsulinemia of nonobese type 2 diabetic MKR mice. Twelve to 14-week-old hyperglycemic MKR mice were gavaged daily with MK-626 (3 mg/kg body weight) or vehicle (0.5% methyl cellulose (MC)) for 2 weeks. MK-626-treated mice displayed no change in body weight or adverse reactions, suggesting good tolerance of the drug. Fed blood glucose was significantly reduced over the 2-week experiment; however, it was also reduced in the MC group, suggesting an effect of gavage alone. Fed plasma insulin and glucagon levels and glucose tolerance of MK-626-treated mice were similar to those of MC mice. Therefore, treatment with MK-626 did not correct the prolonged hyperglycemia and impaired glucose tolerance of MKR mice.     

Angiotensin II‐induced redox‐sensitive SGLT1 and 2 expression promotes high glucose‐induced endothelial cell senescence

High glucose (HG)‐induced endothelial senescence and dysfunction contribute to the increased cardiovascular risk in diabetes. Empagliflozin, a selective sodium glucose co‐transporter2 (SGLT2) inhibitor, reduced the risk of cardiovascular mortality in type 2 diabetic patients but the protective mechanism remains unclear. This study examines the role of SGLT2 in HG‐induced endothelial senescence and dysfunction. Porcine coronary artery cultured endothelial cells (ECs) or segments were exposed to HG (25 mmol/L) before determination of senescence‐associated beta‐galactosidase activity, protein level by Western blot and immunofluorescence staining, mRNA by RT‐PCR, nitric oxide (NO) by electron paramagnetic resonance, oxidative stress using dihydroethidium and glucose uptake using 2‐NBD‐glucose. HG increased ECs senescence markers and oxidative stress, down‐regulated eNOS expression and NO formation, and induced the expression of VCAM‐1, tissue factor, and the local angiotensin system, all these effects were prevented by empagliflozin. Empagliflozin and LX‐4211 (dual SGLT1/2 inhibitor) reduced glucose uptake stimulated by HG and H₂O₂ in ECs. HG increased SGLT1 and 2 protein levels in cultured ECs and native endothelium. Inhibition of the angiotensin system prevented HG‐induced ECs senescence and SGLT1 and 2 expression. Thus, HG‐induced ECs ageing is driven by the local angiotensin system via the redox‐sensitive up‐regulation of SGLT1 and 2, and, in turn, enhanced glucotoxicity.     

利格列汀对小鼠脑缺血/再灌注损伤的神经保护作用*

目的: 评估二肽基肽酶4(DPP-4)抑制剂利格列汀对小鼠脑缺血/再灌注(I/R)损伤的神经保护作用。方法: BALB/c小鼠随机分为Sham组、I/R组和利格列汀(2.5、5和10 mg/kg) +I/R组,每组均为8只小鼠。不同剂量利格列汀组小鼠均在I/R前3周连续灌胃给药。采用小鼠脑中动脉闭塞(MCAO)1 h诱导I/R损伤模型,再灌注24 h评估神经功能缺损(n=8)和及梗死体积(n=4);再灌注48 h处死小鼠,检测脑组织中谷胱甘肽(GSH)、丙二醛(MDA)、磷酸化肌醇3激酶(PI3K)、磷酸化蛋白激酶 B(p-Akt)和雷帕霉素靶蛋白(mTOR)含量(n=4)。结果: 与I/R组相比,利他列汀预处理组小鼠再灌注24 h后,神经功能缺损评分和梗死体积明显降低(P＜0.05);小鼠再灌注48 h后,脑内MDA含量明显降低(P＜0.05),而GSH、PI3K、p-Akt和mTOR水平明显升高(P＜0.05)。结论: 利格列汀对I/R小鼠具有神经保护作用,可能是通过激活PI3K/AKT/mTOR通路发挥的作用。     

Surrogating and redirection of pyrazolo[1,5-a]pyrimidin-7(4H)-one core,a novel class of potent and selective DPP-4 inhibitors

The initial focus on characterizing novel pyrazolo[1,5-a]pyrimidin-7(4H)-one derivatives as DPP-4 inhibitors, led to a potent and selective inhibitor compound b2. This ligand exhibits potent in vitro DPP-4 inhibitory activity (IC₅₀: 80?nM), while maintaining other key cellular parameters such as high selectivity, low cytotoxicity and good cell viability. Subsequent optimization of b2 based on docking analysis and structure-based drug design knowledge resulted in d1. Compound d1 has nearly 2-fold increase of inhibitory activity (IC₅₀: 49?nM) and over 1000-fold selectivity against DPP-8 and DPP-9. Further in vivo IPGTT assays showed that compound b2 effectively reduce glucose excursion by 34% at the dose of 10?mg/kg in diabetic mice. Herein we report the optimization and design of a potent and highly selective series of pyrazolo[1,5-a]pyrimidin-7(4H)-one DPP-4 inhibitors.     

Potential Place of SGLT2 Inhibitors in Treatment Paradigms for type 2 Diabetes Mellitus

Objective: Following the first Food and Drug Administration (FDA) approval in 2013, sodium glucose cotransporter 2 (SGLT2) inhibitors have generated much interest among physicians treating patients with type 2 diabetes mellitus (T2DM). Here, the role in treatment with this drug class is considered in the context of T2DM treatment paradigms.Methods: The clinical trials for the SGLT2 inhibitors are examined with a focus on canagliflozin, dapagliflozin, and empagliflozin.Results: Evidence from clinical trials in patients with T2DM supports the use of SGLT2 inhibitors either as monotherapy or in addition to other glucose-lowering treatments as adjuncts to diet and exercise, and we have gained significant clinical experience in a relatively short time.Conclusion: The drugs appear to be useful in a variety of T2DM populations, contingent primarily on renal function. Most obviously, SGLT2 inhibitors appear to be well suited for patients with potential for hypoglycemia or weight gain. In clinical trials, patients treated with SGLT2 inhibitors have experienced moderate weight loss and a low risk of hypoglycemic events except when used in combination with an insulin secretagogue. In addition, SGLT2 inhibitors have been shown to reduce blood pressure, so they may be beneficial in patients with T2DM complicated by hypertension. SGLT2 inhibitors were incorporated into the 2015 American Diabetes Association (ADA)/European Association for the Study of Diabetes (EASD) position statement on the management of hyperglycemia and received an even more prominent position in the American Association of Clinical Endocrinologists (AACE)/American College of Endocrinology (ACE) comprehensive diabetes management guidelines and algorithm.Abbreviations: AE = adverse event A1C = glycated hemoglobin CI = confidence interval CKD = chronic kidney disease DKA = diabetic ketoacidosis DPP-4 = dipeptidyl peptidase 4 eGFR = estimated glomerular filtration rate FDA = Food and Drug Administration FPG = fasting plasma glucose GLP-1 = glucagon-like peptide 1 HDL-C = high-density lipoprotein cholesterol HR = hazard ratio LADA = late-onset autoimmune diabetes of adulthood LDL-C = low-density lipoprotein cholesterol MACE = major adverse cardiovascular events SGLT1 = sodium glucose cotransporter 1 SGLT2 = sodium glucose cotransporter 2 T1DM = type 1 diabetes mellitus T2DM = type 2 diabetes mellitus UACR = urine albumin to creatinine ratio     

Enhanced atherothrombotic formation after oxidative injury by FeCl3 to the common carotid artery in severe combined hyperlipidemic mice

Enhanced susceptibility to atherosclerosis from severe hypertriglyceridemia (HTG) resulting from lipoprotein lipase (LPL) deficiency has been demonstrated in our recent findings which employed a unique mouse model. In the present study we provide further evidence that severe HTG due to LPL deficiency also promotes an atherothrombotic response to arterial injury induced by ferric chloride in a severe combined hyperlipidemic mouse model. Methods and results: A mouse model (LPL^−/−XApoE^−/− double knockout, DKO) with severe combined hyperlipidemia was established by crossing ApoE and LPL-deficient mice. The common carotid arteries of ApoE knockout (EKO) and DKO mice were subjected to injury by ferric chloride, and the formation of arterial thrombosis together with various markers were compared in these lesions. DKO mice demonstrated significantly enhanced thrombus formation overlying atherosclerotic plaque after injury, which contained smooth muscle cells, macrophages, and neutral lipid. The area of neointima, mean intima/media ratios, and the percentage of luminal stenosis were significantly greater (P < 0.01) in DKO mice. Compared with EKO mice, the expression of von Willebrand factor (vWF) and plasminogen activator inhibitor type 1 (PAI-1) were increased in DKO mice. Conclusions: Severe combined hyperlipidemia promotes thrombosis after ferric chloride injury to atherosclerotic vessels and HTG plays a major role in the process.     

(3R)-4-[(3R)-3-Amino-4-(2,4,5-trifluorophenyl)butanoyl]-3-(2,2,2-trifluoroethyl)-1,4-diazepan-2-one, a selective dipeptidyl peptidase IV inhibitor for the treatment of type 2 diabetes

Replacement of the triazolopiperazine ring of sitagliptin (DPP-4 IC(50)=18nM) with 3-(2,2,2-trifluoroethyl)-1,4-diazepan-2-one gave dipeptidyl peptidase IV (DPP-4) inhibitor 1 which is potent (DPP-4 IC(50)=2.6nM), selective, and efficacious in an oral glucose tolerance test in mice. It was selected for extensive preclinical development as a potential back-up candidate to sitagliptin.