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Losartan (LST) is a common chemical drug used to treat high blood pressure and reduce the risk of stroke in certain people with heart disease. Danshen, prepared from the dried root and rhizome of Salvia miltiorrhiza Bunge , has been widely used for prevention and treatment of various cardiovascular and cerebrovascular diseases. There are more than 35 formulations containing Danshen indexed in the 2010 Chinese Pharmacopoeia, which are often combined with LST to treat cardiovascular and cerebrovascular diseases in the clinic. The effects of the two major components of Danshen, salvianolic acid B (SA-B) and tanshinone IIA (Tan IIA), on the pharmacokinetics of losartan and its metabolite, EXP3174, in rats were investigated by liquid chromatography coupled with mass spectrometry (LC–MS). Male Sprague-Dawley rats were randomly assigned to 3 groups: LST, LST+SA-B and LST+Tan IIA, and the main pharmacokinetic parameters were estimated after oral administration of LST, LST+SA-B and LST+Tan IIA. It was found that there are significant differences in the pharmacokinetic parameters among the three groups: C max , t 1/2 , AUC , AUMC in the LST+SA-B group was smaller than those in group LST, while larger in group LST+Tan IIA. Further, the effects of SA-B and Tan IIA on the metabolism of losartan was also investigated using rat liver microsomes in vitro . The results indicated that SA-B can induce the metabolism of LST, while Tan IIA can inhibit the metabolism of LST in rat liver microsomes in vitro by regulating activities of CYP450 enzymes. In addition, the effect of SA-B and Tan IIA on CYP3A4 and CYP2C9 expression was studied in Chang liver cells by western-blotting and Real-time PCR. It was concluded that the two components of Danshen, SA-B and Tan IIA have different influences on the metabolism of LST: SA-B can obviously speed up the metabolism of LST by inducing CYP3A4/CYP2C9 activities and expression, however, Tan IIA can slow down the metabolism of LST by inhibiting CYP3A4/CYP2C9 activities. [ABSTRACT FROM AUTHOR]

A novel method for the screening of 151 drugs of abuse and toxic compounds in human whole blood has been developed and validated by online solid-phase extraction with liquid chromatography coupled to time-of-flight mass spectrometry. Analytes were extracted and separated by using a fully automated online solid-phase extraction liquid chromatography system with total chromatographic run time of 26 min. Time-of-flight mass spectrometry screening of 151 drugs of abuse and toxic compounds was performed in a full-scan ( m/z 50-800) mode using an MSE acquisition of molecular ions and fragment ions data at two collision energies (one was 6 eV and another one was in the range of 5-45 eV). The compounds were identified based on retention times and exact mass of molecular ions and fragment ions. The limit of detection ranged from 1 to 100 ng/mL and the recovery of the method ranged from 6.3 to 163.5%. This method is proved to be a valuable screening method allowing fast and specific identification of drugs in human whole blood. [ABSTRACT FROM AUTHOR]

A method for separation and determination of 32 fentanyl‐related substances, including seven sets of isomeric fentanyl analogues, was developed using ultra‐high‐performance liquid chromatography coupled with quadrupole‐orbitrap high‐resolution mass spectrometry. The collision energy, chromatographic column, and mobile phase were optimized. All compounds were efficiently flushed out of a universal C18 column with a soft gradient consisting of solvent A (2 mM ammonium formate and 0.1% formic acid in water) and solvent B (2 mM ammonium formate and 0.1% formic acid in methanol) in only 20 min, achieving excellent resolution. Detection and analysis were carried out simultaneously in the positive ion mode using the full scan and data‐dependent tandem mass spectrometry modes with a normalized collision energy of 40. The method was validated in terms of limit of detection, limit of quantification, linearity, accuracy, and precision. For all fentanyl‐related substances, the limit of detection (0.5 ng/mL) and limit of quantification (1 ng/mL) were adequate for screening and quantification in daily drug control. Calibration curves for all compounds were established in the range of 1–500 ng/mL. The intra‐ and interday precision (RSD%) were within 0.4–2.3 and 0.7‐2.7%, respectively. The accuracy ranged from 99 to 106%. The method was applied to analyze seized drug samples. [ABSTRACT FROM AUTHOR]

Saposhnikovia divaricata (SD), a Chinese crude drug, has long been recognized for therapeutic effect to rheumatoid arthritis (RA). At present, the mechanisms of SD treatment in RA have not been fully understood especially on the perspective of metabolomics. Aim of the study : To study the pharmacodynamic effects of Saposhnikovia divaricata decoction on CIA rats, and explore the therapeutic mechanism by metabolomics methods. Wistar rats were randomly divided into normal group, CIA model group, dexamethasone group and SD decoction groups (10 g crude drug/kg, 5 g crude drug/kg and 2.5 g crude drug/kg of SDD). Body weight, arthritis scores, serum cytokine levels and histopathological parameters of rats were assessed. A metabolomics method based on ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOFMS) was established to collect the metabolic profiles of rats and explore the metabolic changes that occurred after SDD treatment. SDD showed its protective effect on the affected joints, especially in the middle dosage group of SDD. Eighteen and 13 potential biomarkers for the SDD treatment of CIA rats were identified in the plasma and urine, respectively. SDD could regulate the disturbed metabolic pathways including tryptophan metabolism, glycerophospholipid catabolism, primary bile acid biosynthesis and fatty acid metabolism. In summary, SDD treatment could effectively alleviate symptoms of RA and regulate metabolic disorders in CIA rats. Image 1 • Saposhnikovia divaricata decoction could effectively alleviate symptoms of CIA rats. • Differentially biomarkers were identified for the SDD treatment of CIA. • Saposhnikovia divaricata decoction could regulate the disturbed metabolic pathways. [ABSTRACT FROM AUTHOR]