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

Abstract

Tryptamines can occur naturally in plants, mushrooms, microbes, and amphibians. Synthetic tryptamines are sold as new psychoactive substances (NPS) because of their hallucinogenic effects. When it comes to NPS, metabolism studies are of crucial importance, due to the lack of pharmacological and toxicological data. Different approaches can be taken to study in vitro and in vivo metabolism of xenobiotica. The zygomycete fungus Cunninghamella elegans (C. elegans) can be used as a microbial model for the study of drug metabolism. The current study investigated the biotransformation of four naturally occurring and synthetic tryptamines [N,N-Dimethyltryptamine (DMT), 4-hydroxy-Nmethyl-N-ethyltryptamine (4-HO-MET), N,N-di allyl-5-methoxy tryptamine (5-MeO-DALT) and 5-methoxy-N-methyl-N-isoporpoyltryptamine (5-MeO-MiPT)] in C. elegans after incubation for 72 hours. Metabolites were identified using liquid chromatography-high resolution-tandem mass spectrometry (LC-HR-MS/MS) with a quadrupole time-of-flight (QqTOF) instrument. Results were compared to already published data on these substances. C. elegans was capable of producing all major biotransformation steps: hydroxylation, N-oxide formation, carboxylation, deamination, and demethylation. On average 63% of phase I metabolites found in the literature could also be detected in C. elegans. Additionally, metabolites specific for C. elegans were identified. Therefore, C. elegans is a suitable complementary model to other in vitro or in vivo methods to study the metabolism of naturally occurring or synthetic tryptamines. KEYWORDS fungi Cunninghamella elegans, metabolism, NPS, tryptamines 1 | INTRODUCTIONMetabolism studies are of essential importance in clinical and forensic toxicology, especially when designer drugs or new psychoactive substances (NPS) are the target substrate as very little is known about their pharmacology and toxicology. When a drug of abuse is consumed, the compound is metabolized. General unknown screening analysis should be able to detect metabolites besides parent drugs, the latter which might not even be detectable a few hours after drug consumption. Hence, when developing methods for the detection of a substance of abuse, the main metabolites are used as analytical targets. 1 Therefore, the pharmacological processes and biotransformation of a drug need to be studied. Furthermore, the information about biotransformation of a substance can be used to evaluate its safety and efficacy, because some metabolites have non-negligible psychoactive properties themselves. [2][3][4] Metabolism studies can involve different in vivo and in vitro methods. In vivo methods on humans are difficult to apply because human samples from forensic or clinical cases are rare and human studies raise major ethical concerns (especially in the absence of preclinical safety data). 5 Alternative in vivo methods are animal studies but these are costly and time consuming and require ethical approval.Furthermore, one cannot neglect interspecies differences. In vitro

Recent trends in drugs of abuse metabolism studies for mass spectrometry–based analytical screening procedures

“…Watanabe et al and Leong et al described that C. elegans was able to generate both phase I and II metabolites in case of four out of five synthetic cannabinoids [ 14 , 21 ]. By contrast, Grafinger et al detected only phase I metabolites of four investigated synthetic tryptamines in fungi biomass and growth medium used [ 15 ]. However, it should be considered that different fungus strains were used.…”

Untargeted Metabolic Profiling of 4-Fluoro-Furanylfentanyl and Isobutyrylfentanyl in Mouse Hepatocytes and Urine by Means of LC-HRMS

“…Characterization of drug metabolites is usually performed using in vitro and/or in vivo studies, which can be assisted by in-silico prediction tools to make LC-HRMS data analysis easier [7]. In vitro studies involve incubation of the drugs with human or animal hepatocyte cultures [8,9], human liver preparations [10] or the fungus Caenorhabditis elegans [11], whereas biological samples collected in authentic cases or samples obtained by controlled drug administration to rats, mice and other rodents may be used for in vivo studies. Novel in vivo models such as zebrafish (Danio rerio) larvae have been recently reported as a good alternative for NPS metabolism studies [12].…”

Systematic characterization of metabolic profiles of ingenol in rats by UPLC-Q/TOF-MS and NMR in combination with microbial biotransformation

“…7 According to the guidance of the U.S. Food and Drug Administration (https://www.fda.gov/drugs/guidancecompliance-regulatory-information/guidances-drugs), drug metabolism is a very important part of safety evaluation and a major factor in drug development. [8][9][10] In recent years, the combination of a powerful analytical tool ultra-performance liquid chromatography-quadrupole time-of-ight-mass spectrometry (UPLC-Q/TOF-MS) and a computer-aided identication platform UNIFI (Waters® UNIFI® Scientic Information System), with the advantages of accuracy in mass measurement, high efficacy in separation technique and rapid identication in Fig. 1 The chemical structure of ingenol.…”