Studies on the metabolism and toxicological detection of glaucine, an isoquinoline alkaloid from Glaucium flavum (Papaveraceae), in rat urine using GC‐MS, LC‐MSⁿ and LC‐high‐resolution MSⁿ

Abstract

Glaucine ((S)-5,6,6a,7-tetrahydro-1,2,9,10-tetramethoxy-6-methyl-4H-dibenzo [de,g]quinoline) is an isoquinoline alkaloid and main component of Glaucium flavum (Papaveraceae). It was described to be consumed as recreational drug alone or in combination with other drugs. Besides this, glaucine is used as therapeutic drug in Bulgaria and other countries as cough suppressant. Currently, there are no data available concerning metabolism and toxicological analysis of glaucine. To study both, glaucine was orally administered to Wistar rats and urine was collected. For metabolism studies, work-up of urine samples consisted of protein precipitation or enzymatic cleavage followed by solid-phase extraction. Samples were afterwards measured by liquid chromatography (LC) coupled to low or high-resolution mass spectrometry (HR-MS). The phase I and II metabolites were identified by detailed interpretation of the corresponding fragmentations, which were further confirmed by determination of their elemental composition using HR-MS. From these data, the following metabolic pathways could be proposed: O-demethylation at position 2, 9 and 10, N-demethylation, hydroxylation, N-oxidation and combinations of them as well as glucuronidation and/or sulfation of the phenolic metabolites. For monitoring a glaucine intake in case of abuse or poisoning, the O- and N-demethylated metabolites were the main targets for the gas chromatography-MS and LC-MS(n) screening approaches described by the authors. Both allowed confirming an intake of glaucine in rat urine after a dose of 2 mg/kg body mass corresponding to a common abuser's dose.

GC-MS, LC-MSn, LC-high resolution-MSn, and NMR studies on the metabolism and toxicological detection of mesembrine and mesembrenone, the main alkaloids of the legal high “Kanna” isolated from Sceletium tortuosum

“…The settings were the same as described previously by Meyer et al [10,18], briefly, a Thermo Fisher Scientific (TF, Dreieich, Germany) Dionex LC system coupled to the TF LTQ Orbitrap (OT) equipped with a HESI II source. Separation was performed by a TF Hypersil Gold (15×2.1 mm, 1.9 μm) and gradient elution.…”

“…For identification of phase II metabolites, 1 mL urine (rat urine 20 mg/kg BW drug administration) was processed by SPE (C18) according to References [17] and [10]. Briefly, urine was diluted with 2 mL purified water before loading the sample on a previously conditioned (1 mL methanol, 1 mL water) Isolute Confirm C18 cartridge.…”

“…The reference standards were commercially not available and had to be isolated first from the plant material. In addition, the detectability of mesembrine, mesembrenone, and/or its metabolites should be assessed using the authors' standard urine screening approaches (SUSA) by GC-MS [10][11][12] and LC-MS n [13,14].…”

High-resolution mass spectrometry in toxicology: current status and future perspectives

“…In vivo metabolism of NPS was investigated in recent years by identifying the phase I and II metabolites using HRMS mainly in urine of humans and/or rats Welter et al 2013Welter et al , 2014aWelter et al , b, 2015aMeyer et al 2013bMeyer et al , c, d, e, 2014cMeyer et al , d, 2015Wink et al 2014Wink et al , 2015bWink et al , c, 2016Caspar et al 2015;Michely et al 2015;Welter-Luedeke and Maurer 2015) or in pics (Schaefer et al 2016). Some of these studies showed that the metabolism of rats was qualitatively comparable to that of humans as the rat metabolites could also be detected in authentic human urine from clinical or forensic case work Welter et al 2013Welter et al , 2015bMeyer et al 2013cMeyer et al , 2015Caspar et al 2015;Helfer et al 2015b;Wink et al 2015c).…”

Screening and Identification of Mitragynine and 7-Hydroxymitragynine in Human Urine by LC-MS/MS

“…Lower doses tend to yield a dopaminergic-dominant result or stimulation, while higher doses result in a mu-opioid receptor-dominant effect, which eclipses the dopaminergic expression or physical and emotional hedonia and pain relief [12,24,35,36]. Many analytical approaches have been reported for the separation and identification of kratom, including GC and GC-MS [2,3,[37][38][39], LC and LC-MS [38,[40][41][42][43][44] and CE and CE-MS [43,45,46]. In this study, we report a rapid and effective method for quantification mitragynine and 7-hydroxymitragynine compounds in human urine matrix.…”