Simultaneous determination of 24 antidepressant drugs and their metabolites in wastewater by ultra-high performance liquid chromatography-tandem mass spectrometry.

Antidepressants are a new kind of pollutants being increasingly found in wastewater. In this study, a fast and sensitive ultra-high performance liquid chromatography-tandem mass spectrometry method was developed and validated for the analysis of 24 antidepressant drugs and six of their metabolites in wastewater. This is the first time that the antidepressant residues in wastewater of Beijing (China) were systematically reported. A solid-phase extraction process was performed with 3 M cation disk, followed by ultra-high performance liquid chromatography-tandem mass spectrometry measurements. The chromatographic separation and mass parameters were optimized in order to achieve suitable retention time and good resolution for analytes. All compounds were satisfactorily determined in one single injection within 20 min. The limit of quantification (LOQ), linearity, and extraction recovery were validated. The LOQ for analytes were ranged from 0.02 to 0.51 ng/mL. The determination coefficients were more than 0.99 within the tested concentration range (0.1-25 ng/mL), and the recovery rate for each target compound was ranged from 81.2% to 118% at 1 ng/mL. This new developed method was successfully applied to analysis the samples collected from Beijing municipal wastewater treatment plants. At least ten target antidepressants were found in all samples and the highest mean concentration of desmethylvenlafaxin was up to 415.6 ng/L.

The adenosine derivative 2',3',5'-tri-O-acetyl-N6-(3-hydroxylaniline) adenosine activates AMPK and regulates lipid metabolism in vitro and in vivo.

AIMS: Our overall objective was to investigate the effect of the adenosine derivative 2',3',5'-tri-O-acetyl-N6-(3-hydroxylaniline) adenosine (WS010117) on AMP-activated protein kinase (AMPK) activation and lipid metabolism and to also assess the underlying mechanisms involved in these processes. MAIN METHODS: HepG2 cells and hamsters fed a high-fat diet were used to test the effects of WS010117 on lipid metabolism. Western blots, chemical intervention, HPLC, SAMS peptide assay, (14)C-labelled acetate and palmitate assays, molecular docking assay and siRNA targeting the AMPK γ1 subunit were used to investigate the effect of WS010117 on AMPK activation as well as the underlying mechanism involved in this activation. KEY FINDINGS: WS010117 treatment resulted in the dose-dependent activation of AMPK in HepG2 cells, increasing lipid oxidation and decreasing lipid biosynthesis. In hamsters that were fed a high-fat diet, WS010117 treatment (1.5-6 mg/kg) significantly inhibited the increase in lipid accumulation. WS010117-induced AMPK activation was essentially abolished by treatment with compound C, and the addition of WS010117 did not alter the intracellular AMP:ATP ratio. In HeLa cells endogenously lacking LKB1, WS010117-mediated AMPK activation was not impaired, even following co-treatment with STO-609, a selective inhibitor of Ca(2+)/calmodulin-dependent protein kinase kinase (CaMKK). The results from the molecular docking assays and experiments targeting the AMPK γ1 subunit with siRNA indicated that WS010117 may activate AMPK by binding to and regulating the γ subunit of AMPK. SIGNIFICANCE: Our data indicate that WS010117 can regulate lipid metabolism through the activation of AMPK. WS010117 may activate AMPK by binding to and regulating the AMPK γ subunit.