1,720,982 research outputs found
Simultaneous chemo- and enantio-separation of 2-, 3- and 4-chloro-methcatinones (CMCs) and 2-, 3- and 4-methylmethcathinones (MMCs), their isomers and major phase-1 metabolites in oral fluid of drug abusers using enantioselective high-performance liquid chromatography tandem mass-spectrometry (UHPLC-MS/MS)
No full textSono stati sviluppati nuovi metodi analitici per la separazione simultanea chemo- ed enantioselettiva di 2-, 3- e 4-clorometcatinoni (CMC) e 2-, 3- e 4-metilmetcatinoni (MMC) utilizzando cromatografia liquida ad alte prestazioni accoppiata a spettrometria di massa tandem (HPLC-MS/MS). I metodi consentono di identificare in modo affidabile gli isomeri di posizione e di quantificare enantioselettivamente questi catinoni sintetici e i loro principali metaboliti di fase 1 in matrici biologiche.
Per i CMC, il 3-CMC è risultato l’isomero più frequentemente rilevato, mentre non sono stati osservati casi di abuso di 2-CMC. L'analisi enantiomerica ha indicato che queste sostanze sono principalmente consumate in forma racemica.
Per i MMC, sono emerse discrepanze tra i risultati dello screening non selettivo iniziale e l'analisi enantioselettiva successiva. Il mefedrone (4-MMC) è stato confermato in un solo campione, mentre il 3-MMC e il 2-MMC sono stati rilevati in sei e dodici campioni rispettivamente, con quattro campioni contenenti entrambi. Inoltre, il metodo ha permesso una parziale separazione enantioselettiva dei metaboliti dei MMC, inclusi i derivati N-demetilati (nor-MMC) e i diidrometaboliti, oltre alla differenziazione di isomeri strutturali come bufedrone, metanfepromone ed etcatinone.Novel analytical methods were developed for the simultaneous chemo- and enantioseparation of 2-, 3-, and 4-chloromethcathinones (CMCs) and 2-, 3-, and 4-methylmethcathinones (MMCs) using high-performance liquid chromatography coupled with tandem mass spectrometry (HPLC-MS/MS). The methods reliably identifies positional isomers and enables enantioselective quantification of these synthetic cathinones and their major phase-1 metabolites in biological matrices.
For CMCs, 3-CMC was the most frequently detected isomer, while no cases of 2-CMC abuse were observed. Enantiomeric analysis suggested that these substances were primarily consumed in racemic forms.
For MMCs, some discrepancies between initial non-selective screening results and enantioselective re-analysis were observed. While mephedrone (4-MMC) was confirmed in only one sample, 3-MMC and 2-MMC were detected in six and twelve samples, respectively, with four samples containing both. Furthermore, the method enabled partial enantioseparation of MMC metabolites, including N-demethyl derivatives (nor-MMCs) and dihydrometabolites, as well as differentiation of structural isomers such as buphedrone, methamfepramone, and ethcathinone.
These fast, robust methods enhances the enantioselective and isomeric analysis of synthetic cathinones, improving the reliability of toxicological assessments in clinical and forensic contexts
Exposure to Synthetic Psychoactive Substances: A Potential Cause for Increased Human Hepatotoxicity Markers
Full text linkBackground: Approximately 30 million people worldwide consume new psychoactive substances (NPS), creating a serious public health issue due to their toxicity and potency. Drug-induced liver injury is the leading cause of liver disease, responsible for 4% of global deaths each year.
Content: A systematic literature search revealed 64 case reports, in vitro and in vivo studies on NPS hepatotoxicity. Maximum elevated concentrations of aspartate aminotransferase (136 to 15 632 U/L), alanine transaminase (121.5 to 9162 U/L), total bilirubin (0.7 to 702 mg/dL; 0.04 to 39.03 mmol/L), direct (0.2-15.1 mg/dL; 0.01-0.84 mmol/L) and indirect (5.3 mg/dL; 0.29 mmol/L) bilirubin, alkaline phosphatase (79-260 U/L), and gamma-glutamyltransferase (260 U/L) were observed as biochemical markers of liver damage, with acute and fulminant liver failure the major toxic effects described in the NPS case reports. In vitro laboratory studies and subsequent in vivo NPS exposure studies on rats and mice provide data on potential mechanisms of toxicity. Oxidative stress, plasma membrane stability, and cellular energy changes led to apoptosis and cell death. Experimental studies of human liver microsome incubation with synthetic NPS, with and without specific cytochrome P450 inhibitors, highlighted specific enzyme inhibitions and potential drug-drug interactions leading to hepatotoxicity.
Summary: Mild to severe hepatotoxic effects following synthetic NPS exposure were described in case reports. In diagnosing the etiology of liver damage, synthetic NPS exposure should be considered as part of the differential diagnosis. Identification of NPS toxicity is important for educating patients on the dangers of NPS consumption and to suggest promising treatments for observed hepatotoxicity
Identification of alexamorelin consumption biomarkers using human hepatocyte incubations and high-resolution mass spectrometry
No full textAlexamorelin is a synthetic peptide and growth hormone secretagogue (GHS) with potential performance-enhancing properties, making its use and abuse a topic of interest in clinical research and doping monitoring. Alexamorelin mimics the natural peptide hormone ghrelin by binding to the GHS type 1a receptor (GHS-R1a) in the pituitary gland, thereby promoting endogenous growth hormone release. Identifying alexamorelin and/or its metabolite biomarkers is crucial for effective doping controls. The purpose of this study was to determine and characterize biomarkers associated with alexamorelin intake. In silico metabolite predictions were performed using GLORYx freeware, and in vitro incubations were conducted with pooled human hepatocytes from 10 donors. Samples were analyzed using liquid chromatography-high-resolution tandem mass spectrometry (LC-HRMS/MS), with data processed through Thermo Scientific's Compound Discoverer. GLORYx predicted 21 single-reaction metabolites. N-Acetylation was identified as the primary transformation, with the highest probability score (98%), and occurring either at the C-terminal Ala or the N-terminal Lys. Other predicted transformations included N-oxidation, hydroxylation, amide hydrolysis, oxidative deamination, and phase II N-glucuronidation, with probability scores below 40%. All these transformations were predicted to occur at the two C-terminal (Ala or His) or N-terminal (D-Phe or Lys) amino acids. After 3 h of incubation with hepatocytes, only one metabolite (known as examorelin or hexarelin) was detected, resulting from the C-terminal cleavage of the Ala amino acid; this metabolic reaction is mediated by a carboxypeptidase. The alexamorelin signal decreased approximately 150-fold after 3 h, indicating significant hepatic metabolism. However, examorelin itself is a commercially available GHS secretagogue, and thus, it is not specific to alexamorelin consumption. Detecting alexamorelin remains critical to documenting its use
Enantioselective separation techniques in forensic analysis and clinical toxicology
No full textEnantioselective analysis is more demanding compared to non-enantioselective one from the viewpoint of time, effort and resources. At the same time if correctly designed it may bring additional information and value to forensic scientists and clinical toxicologists. This short overview describes difficulties versus the added value of enantioselective separations in forensic analysis and clinical toxicology. The specific requirements of enantioselective analytical methods as applied to forensic analysis are summarized in this review and the various separation techniques that such methods are based on are compared to each other from the perspective of forensic analysis. In the final part, the current challenges in this field are shortly reviewed and future trends are highlighted
In vitro, in vivo metabolism and quantification of the novel synthetic opioid N-piperidinyl etonitazene (etonitazepipne)
No full textObjectives: N-piperidinyl etonitazene (etonitazepipne) is a newly synthesized opioid related to the 2-benzylbenzimidazole analog class. Etonitazepipne has been formally notified and placed under intensive monitoring in Europe in January 2022. Nitazenes have high affinity at mu-opioid receptor (MOR). Etonitazepipne, specifically shows a EC50 of 2.49 nM, suggesting about 50 times higher potency combined with higher efficacy compared to morphine. Antinociceptive potency l ('hot plate test' with rats) was 192-fold greater than that of morphine. Methods: Here we report on a post-mortem case involving etonitazepipne and its quantification using a standard addition method (SAM) through liquid chromatography tandem mass spectrometry (LC-MS/MS). In addition, characterization and identification of phase I human metabolites using in vitro assay based on pooled human liver microsomes (pHLM) was performed along with the analysis of authentic urine samples by means of high-performance liquid chromatography high-resolution tandem mass spectrometry (LC-HRMS/MS). Results: The concentration of etonitazepipne in post-mortem blood and urine was 8.3 and 11 ng/mL, respectively. SAM was validated by assessing the following parameters: intraday and interday repeatability, matrix effect and recovery rate in post-mortem blood. A total of 20 and 14 metabolites were identified after pHLM incubation and urine analysis, respectively. Most pronounced in vitro and in vivo transformations were O-deethylation, hydroxylation, ketone reduction, and combinations thereof. Conclusions: Considering small traces of the parent drug often found in real cases, the identification of metabolic biomarkers is crucial to identify exposure to this drug. O-deethylated, oxidated metabolites, and combination thereof are proposed as urinary biomarkers along with the parent compound
UHPLC-MS-MS Determination of THC, CBD and Their Metabolites in Whole Blood of Light Cannabis Smokers
No full text"Light cannabis" is a product legally sold in Europe with Delta(9)-tetrahydrocannabinol (THC) concentration <0.2% and variable cannabidiol (CBD) content. In this study, we aimed to assess the time courses of THC and metabolites (11-nor-9-carboxy-THC and 11-hydroxy-THC) and CBD and metabolites (CBD-7-oic acid, 7-hydroxy-CBD, 6 alpha-hydroxy-CBD and 6 beta-hydroxy-CBD) in whole blood of 10 healthy participants after smoking one or four light cannabis cigarettes (0.16% THC and 5.8% CBD). Blood samples were collected 0.5-4 h after administration. Blood analysis was performed by reversed-phase ultra-performance liquid chromatography-tandem mass spectrometry in multiple reaction monitoring mode after glucuronide hydrolysis and liquid-liquid extraction in basic and acidic conditions. The method was validated following the most recent guidelines in toxicology: the method was linear, accurate, precise and sensitive (lower limits of quantification ranged from 0.005 to 0.01 ng/mL); carryover, matrix effect, recovery, process efficiency and dilution integrity were also assessed. As previously reported, the main metabolites of THC were THC-COOH and then 11-OH-THC, and the main metabolites of CBD were 7-OH-CBD and then 7-COOH-CBD. The time of the first collection, which likely occurred after the maximal concentration of most of the analytes, and the short monitoring time, up to 4 h after smoking, limited the evaluation of the pharmacokinetic parameters
In silico and in vitro human metabolism of IOX2, a performance-enhancing doping agent
No full textIOX2 is a potent inhibitor of prolyl hydroxylase 2, a key enzyme in the regulation of hypoxia-inducible factor (HIF) and oxygen homeostasis. As such, it can be used to enhance athletic performance and is currently banned by the World Anti-Doping Agency (WADA). Detection of metabolites is critical to demonstrate drug use in doping. However, there is currently little data on IOX2 human metabolism. Our aim was to identify relevant biomarkers of IOX2 use in humans. For this purpose, IOX2 was incubated with 10-donor-pooled human hepatocytes for 3 h, incubates were analyzed by liquid chromatography-high-resolution tandem mass spectrometry (LC-HRMS/MS), and LC-HRMS/MS data were screened with Compound Discoverer (Thermo Scientific) for a comprehensive identification of IOX2 metabolites. Additionally, IOX2 human metabolites were predicted with GLORYx open-access software (University of Hamburg, Germany) to assist in the LC-HRMS/MS analysis and data mining. Thirteen metabolites were identified, oxidation at the quinolinyl group, O-glucuronidation, and combinations being predominant biotransformations. The results were consistent with previous animal studies and a single case of oral microdose administration. We suggest hydroxyquinolinyl-IOX2 as major biomarker of IOX2 use in biological samples, glucuronide hydrolysis being critical to increase IOX2 and hydroxyquinolinyl-IOX2 detectability in urine
Biomarkers of 4-hydroxy-N,N-methylpropyltryptamine (4-OH-MPT) intake identified from human hepatocyte incubations
No full textBackground: 4-Hydroxy-N,N-methylpropyltryptamine (4-OH-MPT) is a psychedelic tryptamine whose use is regulated in several countries. Due to unspecific effects, consumption can be ascertained only through toxicological analyses. However, the trace amounts of tryptamines are usually challenging to detect in biological samples. 4-OH-MPT metabolism was characterized to identify optimal metabolite markers of intake in clinical/forensic toxicology. Research design and methods: 4-OH-MPT was incubated with 10-donor-pooled human hepatocytes to simulate in vivo conditions; samples were analyzed by liquid chromatography-high-resolution tandem mass spectrometry (LC-HRMS/MS), and data were processed with Compound Discoverer from Thermo Scientific. LC-HRMS/MS and data mining were supported by in silico metabolite predictions (GLORYx). Results: Three phase I and four phase II metabolites were identified, including N-oxidation and N-demethylation at the alkylamine chain, and O-glucuronidation and sulfation at the hydroxylindole core. Conclusions: 4-OH-MPT metabolic fate was consistent with the human metabolism of tryptamine analogues: we suggest 4-OH-MPT-N-oxide and 4-hydroxy-N,N-propyltryptamine (4-OH-PT) as metabolite biomarkers of 4-OH-MPT consumption after glucuronide/sulfate hydrolysis in biological samples to improve detection of 4-OH-MPT and phase I metabolites; 4-OH-MPT-glucuronide is suggested as an additional biomarker when hydrolysis is not performed. Further research on the metabolism of structural analogues is necessary to evaluate the specificity of 4-OH-MPT metabolite biomarkers
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