Introduction Oral anticoagulation is an effective therapy to prevent and treat thromboembolic events. So far, Vitamin K antagonists have been the main drug of choice. Recently, the advent of the direct oral anticoagulants (DOAC) has changed medical practice significantly; nevertheless all anticoagulants are associated with an increased risk of bleeding. Bleeding management can be achieved through established therapies; however specific antidotes are not yet available for these agents to further facilitate patient management in cases needed. Previously the dabigatran antidote (idarucizumab) has demonstrated immediate, complete and sustained reversal of dabigatran induced anti-coagulation in healthy male volunteers. In the present study it was determined whether and to what extent doses of up to 5 g idarucizumab would reverse the anticoagulant effects of dabigatran in male and female healthy mid-aged, elderly and renally impaired volunteers. In addition, it was tested whether oral intake of dabigatran etexilate 24 hrs after idarucizumab treatment could restore dabigatran related anticoagulation. It was further tested if a second administration of idarucizumab 2 months later was safe and well tolerated. Methods Safety, tolerability, pharmacokinetics (PK) and pharmacodynamics (PD) of idarucizumab were investigated in a randomized, double-blind, placebo controlled two-way cross-over study in 46 male and female volunteers. Dabigatran etexilate (DE), 220 mg bid in healthy subjects and 150 mg bid in subjects with mild or moderate renal impairment (CLCR60 to <90 or 30 to <60 [mL/min], respectively) was given over 4 days to achieve the steady state conditions. Idarucizumab doses of 1 g, 2.5 g, 5 g or 5 g given as 2x2.5 g one hour apart were administered as 5 min i.v. infusion 2 hrs after the last dose of DE. Concentrations of unbound dabigatran were determined as a measure of pharmacologically active dabigatran. The anticoagulant effect of dabigatran and its reversal were assessed by coagulation time measurements, including diluted Thrombin Time (dTT, Hemoclot® DTI assay), Ecarin Clotting Time (ECT) and activated Partial Thromboplastin Time (aPTT). Results All administered doses of idarucizumab were safe and well tolerated. PK measurements of unbound dabigatran indicated that idarucizumab binding and thus reversal of the anticoagulant effect of dabigatran occurred immediately after end of infusion. Prolongation of clotting times induced by dabigatran was reversed to baseline at the end of the 5 minute infusion of the antidote. This was consistently demonstrated by all clotting assays. Sustained reversal over the entire observation period was observed for idarucizumab doses of 2.5 g, 5 g and 2x2.5 g. For the 1g dose, there was partial return of dabigatran induced anticoagulation around 2-4 hours after i.v. infusion. Also a second administration of idarucizumab (two months after the first) was safe and resulted in complete reversal. In addition, PD and PK measurements at selected time points and in comparison to placebo treatment confirmed that effective dabigatran anticoagulation could be re-established 24 hours after administration of idarucizumab. Conclusions The dabigatran antidote, idarucizumab, was well tolerated under all conditions tested. The administration of 5 g or 2x2.5 g led to sustained reversal of dabigatran induced anticoagulation in male and female subjects of different age and renal function. In addition, idarucizumab administered 2 months apart achieved the same degree of reversal. Dabigatran anticoagulation could be re-established 24 hrs after idarucizumab dosing. These results support the use of a total dose of 5 g idarucizumab as an effective dose in further clinical testing. Disclosures Glund: Boehringer Ingelheim: Employment. Off Label Use: Idarucizumab, a specific antidote for dabigatran, is in clinical development.. Stangier:Boehringer Ingelheim: Employment. Schmohl:Boehringer Ingelheim: Employment. Moschetti:Boehringer Ingelheim: Employment. Haazen:SGS Life Science Services (contracted by Boehringer Ingelheim to conduct the study): Employment. De Smet:SCS Boehringer Ingelheim Comm. V.: Employment. Gansser:Boehringer Ingelheim: Employment. Norris:Boehringer Ingelheim: Employment. Lang:Boehringer Ingelheim: Employment. Reilly:Boehringer Ingelheim: Employment.

Leptin regulates food intake and energy expenditure by activating the long form of the leptin receptor (LepRb). Leptin also regulates glucose homeostasis by improving whole-body insulin sensitivity, but the mechanism remains undefined. Leptin action is mediated by phosphorylation of several tyrosine residues on LepRb. LepRb-Tyr985 plays an important role in the attenuation of LepRb signaling. We determined the contribution of LepRb-Tyr985-mediated signals to leptin action on insulin sensitivity using LepRb-Tyr985 mutant mice (l/l mice). Glucose tolerance and whole-body insulin-mediated glucose utilization were determined in wild-type (+/+) and l/l mice. Glucose tolerance was unaltered between female +/+ and l/l mice but enhanced in the male l/l mice. Serum insulin concentration was decreased at baseline and 15 min after a glucose injection in female l/l vs. +/+ mice (P < 0.05) but unaltered in the male l/l mice. However, basal and insulin-stimulated glucose transport in isolated soleus and extensor digitorum longus muscle was similar between +/+ and l/l mice, indicating skeletal muscle insulin sensitivity in vitro was not enhanced. Moreover, euglycemic-hyperinsulinemic clamps reveal hepatic, rather than peripheral, insulin sensitivity is enhanced in female l/l mice, whereas male l/l mice display both improved hepatic and peripheral insulin sensitivity. In conclusion, signals emanating from leptin receptor Tyr985 control hepatic insulin sensitivity in both female and male l/l mice. Lack of LepRb-Tyr985 signaling enhances whole-body insulin sensitivity partly through increased insulin action on the suppression of hepatic glucose production.

We investigated the direct effect of a nitric oxide donor (spermine NONOate) on glucose transport in isolated human skeletal muscle and L6 skeletal muscle cells. We hypothesised that pharmacological treatment of human skeletal muscle with N-(2-aminoethyl)-N-(2-hydroxy-2-nitrosohydrazino)-1,2-ethylenediamine (spermine NONOate) would increase intracellular cyclic GMP (cGMP) levels and promote glucose transport.

Die Zunahme an Fettgewebe bei der Entwicklung von Adipositas ist sowohl auf die Erhöhung der Adipozytenzahl als auch auf die Zunahme der Größe von Adipozyten zurückzuführen. Adipozyten stammen von multipotenten Stammzellen mesodermalen Ursprungs ab, die sich bei geeigneter Stimulierung über Präadipozyten zu Adipozyten entwickeln.

Derangements in whole body glucose and lipid metabolism, accompanied by insulin resistance, are key features of obesity and the metabolic syndrome. A role for inflammation as a causative factor is an emerging concept in the field of metabolic disease. Research has centred on identifying important inflammatory markers, and tumour necrosis factor‐α has been highlighted as a key mediator of insulin resistance, as well as interleukin‐6 (IL‐6). A parallel ongoing endeavour is the unravelling of molecular mechanisms underlying the beneficial effects of physical exercise on whole body glucose and lipid metabolism. Release of IL‐6 from the contracting skeletal muscle has been proposed to be one of the molecular signals promoting the beneficial exercise‐induced effects. These two opposing views of IL‐6 underscore that the role of IL‐6 in whole body physiology is incompletely resolved. This review aims at summarizing the current data on mechanisms by which IL‐6 may impact on glucose and lipid metabolism.

Aims/hypothesis Exercise enhances insulin-stimulated glucose transport in skeletal muscle through changes in signal transduction and gene expression. The aim of this study was to assess the impact of acute and short-term exercise training on whole-body insulin-mediated glucose disposal and signal transduction along the canonical insulin signalling cascade.Methods A euglycaemic-hyperinsulinaemic clamp, with vastus lateralis skeletal muscle biopsies, was performed at baseline and 16 h after an acute bout of exercise and short-term exercise training (7 days) in obese non-diabetic (n=7) and obese type 2 diabetic (n=8) subjects.Results Insulin-mediated glucose disposal was unchanged following acute exercise in both groups. Short-term exercise training increased insulin-mediated glucose disposal in obese type 2 diabetic (p < 0.05), but not in obese non-diabetic subjects. Insulin activation of (1) IRS1, (2) IRS2, (3) phosphotyrosine-associated phosphatidylinositol-3 kinase activity and (4) the substrate of phosphorylated Akt, AS160, a functional Rab GTPase activating protein important for GLUT4 (now known as solute carrier family 2 [facilitated glucose transporter], member 4 [SLC2A4]) translocation, was unchanged after acute or chronic exercise in either group. GLUT4 protein content was increased in obese type 2 diabetic subjects (p < 0.05), but not in obese non-diabetic subjects following chronic exercise.Conclusions/interpretation Exercise training increased whole-body insulin-mediated glucose disposal in obese type 2 diabetic patients. These changes were independent of functional alterations in the insulin-signalling cascade and related to increased GLUT4 protein content.

We identified signaling pathways by which IL-6 regulates skeletal muscle differentiation and metabolism. Primary human skeletal muscle cells were exposed to IL-6 (25 ng/ml either acutely or for several days), and small interfering RNA gene silencing was applied to measure glucose and fat metabolism. Chronic IL-6 exposure increased myotube fusion and formation and the mRNA expression of glucose transporter 4, peroxisome proliferator activated receptor (PPAR)alpha, PPARdelta, PPARgamma, PPARgamma coactivator 1, glycogen synthase, myocyte enhancer factor 2D, uncoupling protein 2, fatty acid transporter 4, and IL-6 (P < 0.05), whereas glucose transporter 1, CCAAT/enhancer-binding protein-alpha, and uncoupling protein 3 were decreased. IL-6 increased glucose incorporation into glycogen, glucose uptake, lactate production, and fatty acid uptake and oxidation, concomitant with increased phosphorylation of AMP-activated protein kinase (AMPK), signal transducer and activator of transcription 3, and ERK1/2. IL-6 also increased phosphatidylinositol (PI) 3-kinase activity (450%; P < 0.05), which was blunted by subsequent insulin-stimulation (P < 0.05). IL-6-mediated glucose metabolism was suppressed, but lipid metabolism was unaltered, by inhibition of PI3-kinase with LY294002. The small interfering RNA-directed depletion of AMPK reduced IL-6-mediated fatty acid oxidation and palmitate uptake but did not reduce glycogen synthesis. In summary, IL-6 increases glycogen synthesis via a PI3-kinase-dependent mechanism and enhances lipid oxidation via an AMPK-dependent mechanism in skeletal muscle. Thus, IL-6 directly promotes skeletal muscle differentiation and regulates muscle substrate utilization, promoting glycogen storage and lipid oxidation.

AMP-activated protein kinase (AMPK) is an evolutionarily conserved heterotrimer important for metabolic sensing in all eukaryotes. The muscle-specific isoform of the regulatory γ-subunit of the kinase, AMPK γ3, has an important role in glucose uptake, glycogen synthesis, and fat oxidation in white skeletal muscle, as previously demonstrated by physiological characterization of AMPK γ3 mutant (R225Q) transgenic (TgPrkag3225Q) and γ3 knock-out (Prkag3-/-) mice. We determined AMPK γ3-dependent regulation of gene expression by analyzing global transcription profiles in glycolytic skeletal muscle from γ3 mutant transgenic and knock-out mice using oligonucleotide microarray technology. Evidence is provided for coordinated and reciprocal regulation of multiple key components in glucose and fat metabolism, as well as skeletal muscle ergogenics in TgPrkag3225Q and Prkag3-/- mice. The differential gene expression profile was consistent with the physiological differences between the models, providing a molecular mechanism for the observed phenotype. The striking pattern of opposing transcriptional changes between TgPrkag3225Q and Prkag3-/- mice identifies differentially expressed targets being truly regulated by AMPK and is consistent with the view that R225Q is an activating mutation, in terms of its downstream effects. Additionally, we identified a wide array of novel targets and regulatory pathways for AMPK in skeletal muscle.