Tentative identification of the metabolites of (1-(cyclohexylmethyl)-1H-indol-3-yl)-(2,2,3,3-tetramethylcyclopropyl)methanone, and the product of its thermal degradation, by in vitro and in vivo methods.

Synthetic cannabinoids (SCs), mimicking the psychoactive effects of cannabis, consist of a vast array of structurally diverse compounds. A novel compound belonging to the SC family, (1-(cyclohexylmethyl)-1H-indol-3-yl)-(2,2,3,3-tetramethylcyclopropyl)methanone (named TMCP-CHM in this article) contains a cyclopropane ring that isomerizes during the smoking process, resulting in a ring-opened thermal degradant with a terminal double bond in its structure. Metabolites of TMCP-CHM were tentatively identified in vitro (after incubation of the parent substance with S9 pooled human liver fraction) and in vivo (rat experimental model) studies by accurate-mass liquid chromatography-tandem mass spectrometry (LC-MS/MS). For the identification of the degradant metabolites, and to study biotransformation of parent substance in the human, urine and hair samples from patients, who had ingested the compound and were subsequently admitted to hospital with drug intoxications, were analyzed. Products of mono-, di-, trihydroxylation, carboxylation, and carboxylation combined with hydroxylation of TMCP-CHM and its degradant were detected in human urine. Metabolism of the degradant included addition of water to the terminal double bond followed by dehydration and formation of a cyclic metabolite. Degradant metabolites prevailed in comparison with metabolites of the parent substance in each metabolite group examined, except carboxylation. N-Dealkylated metabolites found in human urine originated only from the degradant. Most of the hydroxy metabolites were detected in human urine in both the free form and as glucuronides. The detection of monohydroxylated (M1.1-M1.3, M/A1.10) and carboxylated/hydroxylated (M4.2, M/A4.3) metabolites of TMCP-CHM and the hydrated form of the monohydroxylated metabolite of the degradant was found to be convenient for routine analysis.

Changes in Gene Expression Profiles in Adult Rat Brain Structures after Neonatal Action of Dipeptidyl Peptidase-IV Inhibitors.

BACKGROUND: Previous studies have shown the development of emotional and motivational disorders, such as anxiety-depression-like disorders with increased aggression in adolescent and adult Wistar rats, occurs after neonatal exposure to the dipeptidyl peptidase-IV (DPP-IV, EC 3.4.14.5) inhibitors diprotin A and sitagliptin (postnatal days 5-18). METHODS: In this study, using real-time PCR, we evaluated changes in the gene expression of serine protease DPP-IV and prolyl endopeptidase (PREP, EC 3.4.21.26; dpp4 and prep genes), monoamine oxidase А (maoA) and B (maoB), and serotonin transporter (SERT; sert) in the brain structures from 3-month-old rats after postnatal action of DPP-IV inhibitors diprotin A and sitagliptin. RESULTS: Dpp4, sert, and maoB gene expression increased and maoA gene expression changed with a tendency to increase in the striatum of rats with neonatal sitagliptin action. The increase of maoA gene expression was also shown in the amygdala. An increase in prep gene expression was found in the striatum of rats with the neonatal action of diprotin A, and a decrease in maoB gene expression was observed in the amygdala. We detected a significant downward trend in sert gene expression in the frontal cortex and amygdala, as well as a tendency to increase in maoA gene expression in the hypothalamus. DISCUSSION: These findings suggest that changes in the expression of the abovementioned genes are associated with the development of anxiety and depression, with increased aggression caused by the neonatal action of diprotin A and sitagliptin.