Maria Andersson1, Xingxing Diao1, Ariane Wohlfarth1,2,3, Karl B Scheidweiler1, Marilyn A Huestis1. 1. Chemistry and Drug Metabolism, IRP, National Institute on Drug Abuse, National Institutes of Health, Baltimore, MD, 21224, USA. 2. Department of Forensic Genetics and Forensic Toxicology, National Board of Forensic Medicine, 58758, Linköping, Sweden. 3. Department of Drug Research, University of Linköping, 58185, Linköping, Sweden.
Abstract
RATIONALE: AMB (methyl (1-pentyl-1H-indazole-3-carbonyl)-L-valinate)) and its fluoro analog 5F-AMB (methyl (1-(5-fluoropentyl)-1H-indazole-3-carbonyl)-L-valinate) are two new synthetic cannabinoids that are structural analogs of AB-PINACA and 5F-AB-PINACA, respectively. 5F-AMB is scheduled as an illicit drug in China, Germany, Singapore and Japan, and no metabolism data are currently available for either drug. The aim of the present work was to investigate the metabolism of AMB and 5F-AMB and propose appropriate markers to identify their intake in clinical or forensic cases. METHODS: AMB and 5F-AMB were incubated in human hepatocytes (10 μmol/L) to generate phase I and II metabolites, which were identified with a TripleTOF 5600(+) high-resolution mass spectrometer. AMB and 5F-AMB metabolic stability studies also were performed with human liver microsomes (HLM) to evaluate metabolic clearances, and to adequately design the human hepatocyte experiment. RESULTS: AMB and 5F-AMB were quickly metabolized in HLM with a 1.1 ± 0.1 and 1.0 ± 0.2 min T1/2, respectively. The predominant metabolic pathway for AMB and 5F-AMB in hepatocytes was ester hydrolysis, and further oxidation and/or glucuronidation. In total, 19 metabolites were identified for AMB and 17 for 5F-AMB. We describe metabolites to differentiate AMB from 5F-AMB, and metabolites that are common to both analytes due to oxidative defluorination of 5F-AMB. CONCLUSIONS: For the first time, AMB and 5F-AMB metabolism profiles were characterized, providing valuable data for identifying these two novel psychoactive substances. The difficulties of differentiating AMB and 5F-AMB from AB-PINACA/5F-AB-PINACA metabolites also were examined. These data improve the interpretation of urinary markers after AMB and 5F-AMB intake. Published in 2016. This article is a U.S. Government work and is in the public domain in the USA. Published in 2016. This article is a U.S. Government work and is in the public domain in the USA.
RATIONALE: AMB (methyl (1-pentyl-1H-indazole-3-carbonyl)-L-valinate)) and its fluoro analog 5F-AMB (methyl (1-(5-fluoropentyl)-1H-indazole-3-carbonyl)-L-valinate) are two new synthetic cannabinoids that are structural analogs of AB-PINACA and 5F-AB-PINACA, respectively. 5F-AMB is scheduled as an illicit drug in China, Germany, Singapore and Japan, and no metabolism data are currently available for either drug. The aim of the present work was to investigate the metabolism of AMB and 5F-AMB and propose appropriate markers to identify their intake in clinical or forensic cases. METHODS:AMB and 5F-AMB were incubated in human hepatocytes (10 μmol/L) to generate phase I and II metabolites, which were identified with a TripleTOF 5600(+) high-resolution mass spectrometer. AMB and 5F-AMB metabolic stability studies also were performed with human liver microsomes (HLM) to evaluate metabolic clearances, and to adequately design the human hepatocyte experiment. RESULTS:AMB and 5F-AMB were quickly metabolized in HLM with a 1.1 ± 0.1 and 1.0 ± 0.2 min T1/2, respectively. The predominant metabolic pathway for AMB and 5F-AMB in hepatocytes was ester hydrolysis, and further oxidation and/or glucuronidation. In total, 19 metabolites were identified for AMB and 17 for 5F-AMB. We describe metabolites to differentiate AMB from 5F-AMB, and metabolites that are common to both analytes due to oxidative defluorination of 5F-AMB. CONCLUSIONS: For the first time, AMB and 5F-AMB metabolism profiles were characterized, providing valuable data for identifying these two novel psychoactive substances. The difficulties of differentiating AMB and 5F-AMB from AB-PINACA/5F-AB-PINACA metabolites also were examined. These data improve the interpretation of urinary markers after AMB and 5F-AMB intake. Published in 2016. This article is a U.S. Government work and is in the public domain in the USA. Published in 2016. This article is a U.S. Government work and is in the public domain in the USA.
Authors: Thomas F Gamage; Charlotte E Farquhar; Ryan J McKinnie; Richard C Kevin; Iain S McGregor; Mark L Trudell; Jenny L Wiley; Brian F Thomas Journal: J Pharmacol Exp Ther Date: 2018-12-14 Impact factor: 4.030
Authors: Xingxing Diao; Jeremy Carlier; Mingshe Zhu; Shaokun Pang; Robert Kronstrand; Karl B Scheidweiler; Marilyn A Huestis Journal: Forensic Toxicol Date: 2016-07-06 Impact factor: 4.096
Authors: Richard C Kevin; Timothy W Lefever; Rodney W Snyder; Purvi R Patel; Thomas F Gamage; Timothy R Fennell; Jenny L Wiley; Iain S McGregor; Brian F Thomas Journal: Drug Test Anal Date: 2017-09-28 Impact factor: 3.345
Authors: Richard C Kevin; Timothy W Lefever; Rodney W Snyder; Purvi R Patel; Timothy R Fennell; Jenny L Wiley; Iain S McGregor; Brian F Thomas Journal: Forensic Toxicol Date: 2017-03-10 Impact factor: 4.096