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Stefan König

University of Bern

4 papers in the library · 72 citations · publishing 2017-2018

Papers

Study of the in vitro and in vivo metabolism of the tryptamine 5‐MeO‐MiPT using human liver microsomes and real case samples

Drug Testing and Analysis July 5, 2017 Katharina Elisabeth Grafinger, Marianne Hädener, Stefan König et al. 31 citations

The synthetic tryptamine 5-MeO-MiPT, a hallucinogenic drug recently abused in Germany and Switzerland, was identified in a case of intoxication involving a naked, agitated, and aggressive man. Metabolites were characterized in pooled human liver microsomes, blood, and urine using LC–HRMS/MS. Seven phase I metabolites were found in vitro; four in blood and seven in urine. The most abundant metabolites resulted from demethylation and hydroxylation. Blood concentration was 160 ng/mL; urine concentration was 3380 ng/mL. Cocaine, cocaethylene, methylphenidate, and ritalinic acid were also detected in urine. Four metabolites—5-MeO-NiPT, 5-OH-MiPT, 5-MeO-MiPT-N-oxide, and OH-5-MeO-MiPT—are recommended as biomarkers for detecting consumption.

DOI: 10.1002/dta.2245 Chemistry Tryptamine Urine Chromatography +9

Investigating the ability of the microbial model Cunninghamella elegans for the metabolism of synthetic tryptamines

Drug Testing and Analysis November 21, 2018 Katharina Elisabeth Grafinger, Andreas Wilke, Stefan König et al. 15 citations

A fungus, Cunninghamella elegans, can mimic human drug metabolism and was tested on four tryptamines: DMT, 4-HO-MET, 5-MeO-DALT, and 5-MeO-MiPT. After 72 hours of incubation, the fungus performed key biotransformation steps like hydroxylation, N-oxide formation, carboxylation, deamination, and demethylation. On average, 63% of phase I metabolites previously reported in the literature were also produced by C. elegans, along with some unique metabolites. The findings suggest C. elegans is a useful complementary model for studying the metabolism of natural and synthetic tryptamines, especially given the lack of pharmacological data for new psychoactive substances.

DOI: 10.1002/dta.2544 Tryptamines Biotransformation Metabolism Hydroxylation +5

In vitro phase I metabolism of three phenethylamines 25D‐NBOMe, 25E‐NBOMe and 25N‐NBOMe using microsomal and microbial models

Drug Testing and Analysis July 3, 2018 Katharina Elisabeth Grafinger, Katja Stahl, Andreas Wilke et al. 13 citations

The metabolism of three hallucinogenic phenethylamines—25D-NBOMe, 25E-NBOMe, and 25N-NBOMe—was investigated using pooled human liver microsomes (pHLM) and the fungus Cunninghamella elegans. In pHLM, 36, 26, and 24 phase I metabolites were identified for 25D-NBOMe, 25E-NBOMe, and 25N-NBOMe, respectively; in C. elegans, 14, 11, and 9 metabolites were found. Major biotransformation steps included oxidative deamination, N-dealkylation, O-demethylation, hydroxylation, and oxidation of alcohols. Unique metabolites included N-oxide and hydroxylamine derivatives, reported for the first time for NBOMe compounds. C. elegans produced all main biotransformation steps observed in human microsomes, suggesting its potential as a model for studying new psychoactive substances.

DOI: 10.1002/dta.2446 Phenethylamines In vitro Microsome Pharmacology +2