A sensitive and simple liquid chromatography-tandem mass spectrometry method was developed and validated for the simultaneous quantification of ticagrelor and its active metabolite, AR-C124910XX from 50 µL human plasma using tolbutamide as an internal standard as per regulatory guidelines. Analytes in plasma were extracted by simple protein precipitation using acetonitrile, followed by chromatographic separation with an Acclaim™ RSLC 120 C₁₈ column (2.2 µm, 2.1 × 100 mm) and a gradient acetonitrile-water mobile phase containing 0.1% formic acid within 8 min. Mass spectrometric detection and quantitation were conducted by selected reaction-monitoring on a negative electrospray ionization mode with the following transitions: m/z 521.11 → 361.10, 477.03 → 361.10, and 269.00 → 169.60 for ticagrelor, AR-C124910XX, and tolbutamide, respectively. The lower limit of quantifications was 0.2 ng/mL with linear ranges of 0.2–2,500 ng/mL (r² ≥ 0.9949) for both analytes. All validation data, including selectivity, cross-talk, precision, accuracy, matrix effect, recovery, dilution integrity, stability, and incurred sample reanalysis, were well within acceptable limits. This assay method was validated using K₂-EDTA as the specific anticoagulant. Also, the anticoagulant effect was tested by lithium heparin, sodium heparin, and K₃-EDTA. No relevant anticoagulant effect was observed. This validated method was effectively used in the determination of ticagrelor and its active metabolite, AR-C124910XX, in plasma samples from patients with myocardial infarction.
Heparin ; Humans ; Lithium ; Mass Spectrometry ; Methods ; Myocardial Infarction ; Pharmacokinetics ; Plasma ; Tolbutamide

As the elderly population is increasing, Alzheimer's disease (AD) has become a global issue and many clinical trials have been conducted to evaluate treatments for AD. As these clinical trials have been conducted and have failed, the development of new theraphies for AD with fewer adverse effects remains a challenge. In this study, we examined the effects of Theracurmin on cognitive decline using 5XFAD mice, an AD mouse model. Theracurmin is more bioavailable form of curcumin, generated with submicron colloidal dispersion. Mice were treated with Theracurmin (100, 300 and 1,000 mg/kg) for 12 weeks and were subjected to the novel object recognition test and the Barnes maze test. Theracurmin-treated mice showed significant amelioration in recognition and spatial memories compared those of the vehicle-treated controls. In addition, the antioxidant activities of Theracurmin were investigated by measuring the superoxide dismutase (SOD) activity, malondialdehyde (MDA) and glutathione (GSH) levels. The increased MDA level and decreased SOD and GSH levels in the vehicle-treated 5XFAD mice were significantly reversed by the administration of Theracurmin. Moreover, we observed that Theracurmin administration elevated the expression levels of synaptic components, including synaptophysin and post synaptic density protein 95, and decreased the expression levels of ionized calcium-binding adapter molecule 1 (Iba-1), a marker of activated microglia. These results suggest that Theracurmin ameliorates cognitive function by increasing the expression of synaptic components and by preventing neuronal cell damage from oxidative stress or from the activation of microglia. Thus, Theracurmin would be useful for treating the cognitive dysfunctions observed in AD.
Aged ; Alzheimer Disease ; Animals ; Cognition ; Colloids ; Curcumin ; Glutathione ; Humans ; Malondialdehyde ; Mice ; Microglia ; Neurons ; Oxidative Stress ; Post-Synaptic Density ; Spatial Memory ; Superoxide Dismutase ; Synaptophysin