Mildronate has been used as antianginal drug in parts of Europe for many years, but its pharmacokinetic (PK) properties in humans remain unclear. This study was designed to assess and compare the PK properties of mildronate capsules after single escalating oral dose and multiple doses in healthy Chinese volunteers. Volunteers were randomly assigned to receive a single dose of 250, 500, 1000, 1250 or 1500 mg of mildronate capsules. Those who received the 500-mg dose continued on the multiple-dose phase and received 500 mg three times a day for 13 days. Plasma drug concentrations were analysed by ultraperformance liquid chromatography coupled with tandem mass spectrometry (UPLC-MS/MS). Tolerability was assessed throughout the study. A total of 40 Chinese volunteers were enrolled in the study. No period or sequence effect was observed. Area under the concentration and C(max) were increased proportionally with the dose levels, whereas t(1/2) and V(d)/f were dependent on the dose. Nonlinear PK properties were found at doses of 250-1500 mg. There was an accumulation after multiple-dose administration. No serious adverse events (AEs) were reported in the PK study. The formulation was well tolerated.
The determination of the concentrations of antiretroviral drugs in hair is believed to be an important means for the assessment of the long-term adherence to highly active antiretroviral therapy. At present, the combination of tenofovir, lamivudine and nevirapine is widely used in China. However, there was no research reporting simultaneous determination of the three drugs in hair. The present study aimed to develop a sensitive method for simultaneous determination of the three drugs in 2-mg and 10-mg natural hair (Method 1 and Method 2). Hair samples were incubated in methanol at 37 °C for 16 h after being rinsed with methanol twice. The analysis was performed on high performance liquid chromatography tandem mass spectrometry with electronic spray ionization in positive mode and multiple reactions monitoring. Method 1 and Method 2 showed the limits of detection at 160 and 30 pg/mg for tenofovir, at 5 and 6 pg/mg for lamivudine and at 15 and 3 pg/mg for nevirapine. The two methods showed good linearity with the square of correlation coefficient >0.99 at the ranges of 416-5000 and 77-5000 pg/mg for tenofovir, 12-5000 and 15-5000 pg/mg for lamivudine and 39-50,000 and 6-50,000 pg/mg for nevirapine. They gave intra-day and inter-day coefficient of variation <15% and the recoveries ranging from 80.6 to 122.3% and from 83.1 to 114.4%. Method 2 showed LOD and LOQ better than Method 1 for tenofovir and nevirapine and matched Method 1 for lamivudine, but there was high consistency between them in the determination of the three drugs in hair. The population analysis with Method 2 revealed that the concentrations in hair were decreased with the distance of hair segment away from the scalp for the three antiretroviral drugs.
Abstract. To investigate the protective effects of acteoside against apoptosis induced by X-ray radiation in human skin fibroblasts (HSFs), the cells were divided into the following groups: Control group; X-ray radiation group; acteoside group, in which the confluent cells were preincubated with 50 µg/ml acteoside for 2 h followed by radiation; and positive control group, in which the cells were preincubated with 50 µg/ml paeoniflorin followed by radiation. For the radiation, HSF cells preincubated with acteoside or paeoniflorin were exposed to X-ray beams at a dose-rate of 3 Gy/min (16 Gy in total). Cell viability, apoptosis and intracellular alteration of redox were monitored by MTT and flow cytometry. Compared with the radiation group, the number of cells arrested at the G0/G1 phase was significantly reduced in the acteoside and paeoniflorin groups, respectively (P<0.05). X-ray radiation induced marked apoptosis in HSF cells and acteoside reversed this effect. Compared with the radiation group, the generation of intracellular reactive oxygen species (ROS) was abrogated by pre-incubation with acteoside or paeoniflorin (P<0.05). In addition, the upregulation of pro-caspase-3 induced by radiation was reversed by acteoside or paeoniflorin. Radiation could induce upregulation of Bax and downregulation of Bcl-2; however, it was reversed completely after administration of acteoside or paeoniflorin. Furthermore, the enhanced expression of ERK and JNK induced by radiation was reversed by acteoside or paeoniflorin. Acteoside could protect the cells from X-ray induced damage through enhancing the scavenging activity of ROS, decreasing the Bax/Bcl-2 ratio and downregulating the activity of procaspase-3, as well as modulating the mitogen-activated protein kinase signaling pathways.
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