xlr-11 and Substance-Related-Disorders

Human hepatocytes possess a wider range of phase I and II drug-metabolizing enzyme activities than other liver tissue-derived products, such as human liver microsomes. Thus, hepatocytes may be useful for predicting the in vivo metabolic fate of new drugs of abuse in humans. Recently, new types of human hepatocytes have been made commercially available for use in drug metabolism studies, such as a liver tumor-derived cell line (HepaRG), and a human induced pluripotent stem cell-derived hepatocyte (h-iPS-HEP). In our laboratory, HepaRG has been used to elucidate the metabolic pathways of XLR-11, a synthetic cannabinoid, and its thermal degradant. In addition, the potential of h-iPS-HEP to metabolize drugs was assessed using fentanyl as a model drug, and indeed, h-iPS-HEP exhibited a pattern for fentanyl metabolite formation similar to that observed in vivo. In addition, the phase I and II drug-metabolizing enzyme activities of HepaRG, h-iPS-HEP, liver-humanized mouse-derived hepatocytes (PXB-cellsTM), and human primary hepatocytes were evaluated and compared. HepaRG showed high phase I and II drug metabolism activities; however, the CYP2D6 activity in these cells was quite low, and therefore h-iPS-HEP lacked O-methylation and conjugation activities. PXB-cells provided optimal results, i.e., these cells are extremely easy to use, and they possess higher phase I and II drug-metabolizing enzyme activities than the other cells tested. Although PXB-cells are contaminated with mouse-derived cells up to a concentration of several percent, this cell system appears to be promising for the prediction of in vivo human metabolism of new drugs of abuse.

Topics: Animals; Cannabinoids; Cell Line; Cytochrome P-450 CYP2D6; Fentanyl; Hepatocytes; Humans; Methylation; Mice; Substance-Related Disorders

Analysis of drugs in hair is often used as a routine method to obtain detailed information about drug ingestion. However, few studies have been conducted on disposition of synthetic cannabinoids including cyclopropylindoles (UR-144 and XLR-11) and their metabolites in hair. XLR-11 has been widely abused in South Korea recently. Identification of metabolites in hair can be an important proof of synthetic cannabinoids use because it can exclude the possibility of passive smoke exposure. In this study, we described a quantitative analytical method of XLR-11 and its metabolites (UR-144, UR-144 N-5-hydroxypentyl metabolite, UR-144 N-4-hydroxypentyl metabolite, UR-144 N-pentanoic acid metabolite and XLR-11 N-4-hydroxypentyl metabolite) in hair by liquid chromatography with ESI-MS/MS. The target analytes were extracted with methanol from washed and cut hair samples and the extracts were evaporated, filtered and analyzed by LC-MS/MS with electrospray ion source in positive-ionization mode. JWH-018-d9 and JWH-018 N-5-hydroxypentyl metabolite-d5 were used as internal standards. Chromatographic separation was completed within 15 min. No interferences were detected in 10 blank hair samples. In intra- and inter-assay precision and accuracy study, CV (%) and bias (%) were below 12. The limit of detection (LOD) was 0.1∼2 pg/mg and the limit of quantification (LOQ) was 0.2-2 pg/mg, respectively. The validation results proved that the method was selective, accurate and precise with acceptable linearity within calibration range. No significant variation was observed by different sources of matrices. This method was applied to hair samples from 14 individual suspects of XLR-11 use. In this result, XLR-11, UR-144, UR-144 N-5-hydroxypentyl metabolite and UR-144 N-pentanoic acid metabolite, XLR-11 N-4-hydroxypentyl metabolite were detected. The concentration of XLR-11 as a parent drug was much higher than other metabolites. UR-144 N-5-hydroxy metabolite and UR-144 N-pentanoic acid were detected mainly in the authentic hair samples from suspected of XLR-11 use. UR-144 N-4- hydroxypentyl metabolite was not detected in all cases.

Topics: Calibration; Cannabinoids; Chromatography, Liquid; Hair; Humans; Indoles; Limit of Detection; Methanol; Pentanoic Acids; Reproducibility of Results; Spectrometry, Mass, Electrospray Ionization; Substance Abuse Detection; Substance-Related Disorders; Tandem Mass Spectrometry

Synthetic cannabinoids are increasingly used in the United States as marijuana substitutes. However, reports of severe toxicity, resulting from their use, are limited. We present the case of acute cerebral infarction following synthetic cannabinoid inhalation.. A 33-year-old man with no significant medical history presented at the emergency department with right-sided weakness and aphasia. He had smoked a synthetic cannabinoid (SC) product called "WTF" prior to the onset of symptoms. Physical examination showed right hemiparesis, dysarthria, and aphasia. Laboratory evaluation, electrocardiography, and computed tomography (CT) of the head were unremarkable. Following administration of intravenous tissue plasminogen activator, his symptoms improved. A repeat head CT showed acute infarction in the left insular cortex. His hypercoagulability panel was unremarkable, and the patient was discharged neurologically intact. Urine toxicology results were unremarkable. Analysis of the product by gas chromatography-mass spectrometry (GC-MS) procedure confirmed the presence of a synthetic cannabinoid known as XLR-11.. XLR-11 has previously been associated with acute kidney injury in humans. However, there are no reports of it causing acute cerebral ischemic events. The close temporal association between XLR-11 inhalation and his stroke is concerning. Acute cerebral infarction may occur after XLR-11 use in healthy patients.

Topics: Acute Disease; Administration, Inhalation; Adult; Brain Ischemia; Cannabinoids; Humans; Male; Stroke; Substance-Related Disorders; United States