13 research outputs found

    In vitro metabolic fate of nine LSD-based new psychoactive substances and their analytical detectability in different urinary screening procedures

    Get PDF
    The market of new psychoactive substances (NPS) is characterized by a high turnover and thus provides several challenges for analytical toxicology. The analysis of urine samples often requires detailed knowledge about metabolism given that parent compounds may either be present only in small amounts or may not even be excreted. Hence, knowledge of the metabolism of NPS is a prerequisite for the development of reliable analytical methods. The main aim of this work was to elucidate for the first time the pooled human liver S9 fraction metabolism of the nine d-lysergic acid diethylamide (LSD) derivatives 1-acetyl-LSD (ALD-52), 1-propionyl-LSD (1P-LSD), 1-butyryl-LSD (1B-LSD), N6-ethyl-nor-LSD (ETH-LAD), 1-propionyl-N6-ethyl-nor-LSD (1P-ETH-LAD), N6-allyl-nor-LSD (AL-LAD), N-ethyl-N-cyclopropyl lysergamide (ECPLA), (2’S,4’S)-lysergic acid 2,4-dimethylazetidide (LSZ), and lysergic acid morpholide (LSM-775) by means of liquid chromatography coupled to high resolution tandem mass spectrometry. Identification of the monooxygenase enzymes involved in the initial metabolic steps was performed using recombinant human enzymes and their contribution confirmed by inhibition experiments. Overall, N-dealkylation, hydroxylation, as well as combinations of these steps predominantly catalyzed by CYP1A2 and CYP3A4 were found. For ALD-52, 1P-LSD, and 1B-LSD deacylation to LSD was observed. The obtained mass spectral data of all metabolites is essential for reliable analytical detection particularly in urinalysis and for differentiation of the LSD-like compounds as biotransformations also led to structurally identical metabolites. However, in urine of rats after the administration of expected recreational doses and using standard urine screening approaches, parent drugs or metabolites could not be detected

    Chemical synthesis, characterisation and in vitro and in vivo metabolism of the synthetic opioid MT-45 and its newly identified fluorinated analogue 2F-MT-45 with metabolite confirmation in urine samples from known drug users

    Get PDF
    © 2018 The Author(s) Purpose: The detection of a novel psychoactive substance, 2F-MT-45, a fluorinated analogue of the synthetic opioid MT-45, was reported in a single seized tablet. MT-45, 2F-, 3F- and 4F-MT-45 were synthesised and reference analytical data were reported. The in vitro and in vivo metabolisms of MT-45 and 2F-MT-45 were investigated. Method: The reference standards and seized sample were characterised using nuclear magnetic resonance spectroscopy, ultra-performance liquid chromatography–quadrupole time of flight mass spectrometry, gas chromatography–mass spectrometry, attenuated total reflectance-Fourier transform infrared spectroscopy and Raman spectroscopy. Presumptive tests were performed and physicochemical properties of the compounds determined. Metabolite identification studies using human liver microsomes, human hepatocytes, mouse hepatocytes and in vivo testing using mice were performed and identified MT-45 metabolites were confirmed in authentic human urine samples. Results: Metabolic pathways identified for MT-45 and 2F-MT-45 were N-dealkylation, hydroxylation and subsequent glucuronidation. The major MT-45 metabolites identified in human in vitro studies and in authenticated human urine were phase I metabolites and should be incorporated as analytical targets to existing toxicological screening methods. Phase II glucuronidated metabolites were present in much lower proportions. Conclusions: 2F-MT-45 has been detected in a seized tablet for the first time. The metabolite identification data provide useful urinary metabolite targets for forensic and clinical testing for MT-45 and allows screening of urine for 2F-MT-45 and its major metabolites to determine its prevalence in case work

    In vitro toxicokinetics and analytical toxicology of three novel NBOMe derivatives - Phase I and II metabolism, plasma protein binding, and detectability in standard urine screening approaches studied by means of hyphenated mass spectrometry

    Get PDF
    Purpose Toxicokinetic studies are essential in clinical and forensic toxicology to understand drug-drug interactions, influence of individual polymorphisms, and elimination routes, as well as to evaluate targets for toxicological screening procedures. An N-(2-methoxybenzyl)-substituted phenethylamines (NBOMe analogues) intake has been associated with severe adverse reactions including deaths. 1-(1-Benzofuran-5-yl)-N-[(2-methoxyphenyl)methyl]propan-2-amine (5-APB-NBOMe), 2-(8-bromo-2,3,6,7-tetrahydrobenzo[1,2-b:4,5-b′]difuran-4-yl)-N-[(5-chloro-2-ethoxyphenyl)methyl]ethan-1-amine (2C-B-FLY-NB2EtO5Cl), and 2-(8-bromo-2,3,6,7-tetrahydrobenzo[1,2-b:4,5-b′]difuran-4-yl)-N-[(2-methoxyphenyl)methyl]ethan-1-amine (2C-BFLY-NBOMe) are three emerging NBOMe analogues, which have encountered on the drugs of abuse market. So far, their toxicokinetic data are completely unexplored. Methods The study included mass spectrometry-based identification of phase I and II metabolites following exposure to the terminally differentiated human hepatocellular carcinoma cells (HepaRG). The determination of enzymes involved in the major phase I/II metabolic steps and determination of plasma protein binding (PPB) was done. Finally, the evaluation of the toxicological detectability by different hyphenated mass spectrometry techniques in standard urine screening approaches (SUSAs) was investigated. Results The compounds were extensively metabolized in HepaRG cells mainly via O-dealkylation, hydroxylation, glucuronidation, and combinations thereof. CYP1A2, 2D6, 2C8, 2C19, and 3A4, were involved in the initial reactions of all investigated compounds. Glucuronidation of the phase I metabolites – when observed - was mainly catalyzed by UGT1A9. The PPB of all compounds was determined to be > 85%. Only the high-resolution mass spectrometry-based SUSA allowed detection of all compounds in rat urine but only via metabolites. Conclusions The toxicokinetic data provided by this study will help forensic and clinical toxicologists to reliably identify these substances in case of abuse and/or intoxication and will allow them a thorough risk assessment

    Global DNA methylation in fetal human germ cells and germ cell tumours: association with differentiation and cisplatin resistance

    No full text
    Differences in the global methylation pattern, ie hyper- as well as hypo-methylation, are observed in cancers including germ cell tumours (GCTs). Related to their precursor cells, GCT methylation status differs according to histology. We investigated the methylation pattern of normal fetal, infantile, and adult germ cells (n = 103) and GCTs (n = 251) by immunohistochemical staining for 5-(m)cytidine. The global methylation pattern of male germ cells changes from hypomethylation to hypermethylation, whereas female germ cells remain unmethylated at all stages. Undifferentiated GCTs (seminomas, intratubular germ cell neoplasia unclassified, and gonadoblastomas) are hypomethylated, whereas more differentiated GCTs (teratomas, yolk sac tumours, and choriocarcinomas) show a higher degree of methylation. Embryonal carcinomas show an intermediate pattern. Resistance to cisplatin was assessed in the seminomatous cell line TCam-2 before and after demethylation using 5-azacytidine. Exposure to 5-azacytidine resulted in decreased resistance to cisplatin. Furthermore, after demethylation, the stem cell markers NANOG and POU5F1 (OCT3/4), as well as the germ cell-specific marker VASA, showed increased expression. Following treatment with 5-azacytidine, TCam-2 cells were analysed using a high-throughput methylation screen for changes in the methylation sites of 14 000 genes. Among the genes revealing changes, interesting targets were identified: ie demethylation of KLF11, a putative tumour suppressor gene, and hypermethylation of CFLAR, a gene previously described in treatment resistance in GCTs. Copyright (C) 2010 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd

    Non-traditional stable isotope behaviors in immiscible silica-melts in a mafic magma chamber

    Get PDF
    Non-traditional stable isotopes have increasingly been applied to studies of igneous processes including planetary differentiation. Equilibrium isotope fractionation of these elements in silicates is expected to be negligible at magmatic temperatures (δ(57)Fe difference often less than 0.2 per mil). However, an increasing number of data has revealed a puzzling observation, e.g., the δ(57)Fe for silicic magmas ranges from 0‰ up to 0.6‰, with the most positive δ(57)Fe almost exclusively found in A-type granitoids. Several interpretations have been proposed by different research groups, but these have so far failed to explain some aspects of the observations. Here we propose a dynamic, diffusion-induced isotope fractionation model that assumes Si-melts are growing and ascending immiscibly in a Fe-rich bulk magma chamber. Our model offers predictions on the behavior of non-traditional stable isotope such as Fe, Mg, Si, and Li that are consistent with observations from many A-type granitoids, especially those associated with layered intrusions. Diffusion-induced isotope fractionation may be more commonly preserved in magmatic rocks than was originally predicted
    corecore