No abstract

The aim of the present study was to investigate the effect of a single dose of NN414 (a selective SUR1/Kir6.2 potassium channel opener). Sixty-four healthy male subjects were enrolled at 8 dose levels (0.625-12.5 mg/kg or placebo). The study consisted of a baseline day and a dosing day. NN414 or placebo was administered in the evening about 10 pm. On both study days, an oral glucose tolerance test (OGTT) was performed following an overnight fast (corresponding to 9 hours postdose), and glucose, insulin, glucagon, and growth hormone concentrations were determined. NN414 was well tolerated, with no clinically relevant changes in safety parameters, although there was an increase in gastrointestinal side effects. NN414 treatment lowered glucose during the OGTT and 24-hour insulin and glucose levels. In conclusion, a single dose of NN414 is associated with improvements in glucose-related parameters in healthy male subjects.

An inflammatory reaction at the site of infusion is a common clinical problem that is observed after the intravenous application of antibiotics and other drugs. The pathomechanism of this infusion-related phlebitis is not fully understood. We analyzed the effects of the three macrolide antibiotics erythromycin, clarithromycin and azithromycin on human endothelial cells in vitro. As a positive control quinupristin/dalfopristin was studied. The cytotoxicity of all substances was analyzed by a modified MTT cytotoxicity assay with 3T3-fibroblasts and EA.hy 926 endothelial cells. Cells were incubated for 10 days with the antibiotics. After adding MTT the optical density was measured which correlates with cell death. Clarithromycin exhibited the strongest cytotoxic effect on EA.hy 926 cells (EC(50) 30 mg/L), followed by azithromycin (EC(50) 40 mg/L), a cytotoxic effect of erythromycin could only be observed at much higher concentrations (EC(50) 310 mg/L). The reaction of the endothelial cells was further analyzed in detail by means of flow cytometry. For these experiments the endothelial cell line EA.hy 926 as well as primary cells (HUVEC) were used. The antigens were stained with fluoresceinisothiocyanat- or phycoerythrin-conjugated monoclonal antibodies for the following surface antigens: CD34, E-selectin (CD62E), ICAM-1 (CD54) and VCAM-1 (CD106). Cells were incubated with the antibiotics at concentrations ranging from 100 to 800 mg/L (clarithromycin and azithromycin) and from 200 to 1,200 mg/L (erythromycin). These concentrations occur under therapeutic conditions at the site of infusion. Cells were incubated for 2 h and analysis was carried out after an additional culture period of 22 h without test compounds. A significantly enhanced expression of all four antigens was observed which was most pronounced at 800 mg/L (erythromycin), 600 mg/L (azithromycin) and 400 mg/L (clarithromycin). A concentration of 800 mg/L erythromycin medium caused an increase of the expression of CD34 (+6%), E-selectin (+5%), ICAM-1 (+14%) and VCAM-1 (+5%). At lower concentrations (600 mg/L) azithromycin provokes a stronger upregulation of the proinflammatory antigens: CD34 (+17%), E-selectin (+18%), ICAM-1 (+27%) and VCAM-1 (+17%). At a concentration of 400 mg/L medium clarithromycin induced a similar effect as erythromycin at twice this concentration: CD34 (+5%), E-selectin (+7%), ICAM-1 (+23%) and VCAM-1 (+4%). Reactions of the HUVECs were less pronounced than those of the EA.hy 926 cells. Cell surface markers involved in interactions between endothelial cells and leukocytes proved to be useful markers to study differences in the proinflammatory potential of the three macrolides. By analysing the upregulation of these antigens on EA.hy 926 cells in vitro the risk of phlebitis could be predictable for other drugs as well.

No abstract

To evaluate the safety and tolerability of high-dose formoterol and salbutamol in patients with chronic obstructive pulmonary disease (COPD). In this two-way crossover, double-blind, double-dummy study, 17 adults with mild-to-moderate COPD were randomized to receive either formoterol 24 microg (2 x 12 microg via Aerolizer), or salbutamol 600 microg (6 x 100 microg via metered-dose inhaler), and the appropriate double-dummy q.i.d. at 4-h intervals for 3 consecutive days (total daily dose: 96 and 2400 microg, respectively). After a 4-7-day washout period, patients were switched to the other treatment. Treatment with high-dose formoterol and salbutamol was equally well tolerated, with no reports of serious adverse events. Both agents were associated with decreased plasma potassium (mean minimum values: 3.4 and 3.3 mmol/l for formoterol and salbutamol, respectively; P=0.914), increased serum glucose (mean maximum values: 9.0 and 8.7 mmol/l, respectively; P=0.373), and small increases in mean QTc interval (mean maximum 439 ms with both treatments; P=0.813). No clinically relevant between-treatment differences in adverse events or laboratory values occurred. Both drugs improved lung function (mean maximum forced expiratory volume in 1s [FEV(1)] 2.6 l with both treatments; P=0.624), with the improvement being significantly greater with formoterol than with salbutamol on all 3 days of treatment (mean area under the curve [AUC](0-24 h) of FEV(1) formoterol vs. salbutamol on days 1-3, all P<0.05). High-dose formoterol via Aerolizer (up to 96 microg/day) has a comparable tolerability profile to that of salbutamol in patients with mild-to-moderate COPD.