Abstract Using primary neuronal cell culture assays, combined with 2‐D gel electrophoresis and capillary LC–MS, we identified differences in proteomes between control and morphine‐treated cells. Statistically significant differences were observed among 26 proteins. Nineteen of them were up‐regulated, while seven were down‐regulated in morphine‐treated cell populations. The identified proteins belong to classes involved in energy metabolism, associated with oxidative stress, linked with protein biosynthesis, cytoskeletal ones, and chaperones. The detected proteins demand further detailed studies of their biological roles in morphine addiction. It is crucial to confirm observed processes in vivo in order to reveal the nature and importance of the biological effect of proteome changes after morphine administration. Further investigations may lead to the discovery of new proteome‐based effects of morphine on living organisms.
Abstract Anxiety disorder is a great challenge for modern psychopharmacology. Although a variety of single drugs are used in the treatment of anxiety, it is important to search for new therapeutics with faster onset of action, fewer side effects, and higher efficacy. In this work, we studied the possible anxiolytic action mechanism of two new arylpiperazine derivatives: compounds 4p N ‐(3‐(4‐(piperonyl)piperazin‐1‐yl)propyl)isonicotinamide and 3o N ‐(2‐(4‐(pyrimidin‐2‐yl)piperazin‐1‐yl)ethyl)picolinamide, focusing on their effects on the GABAergic and 5‐HT systems. The elevated plus‐maze test (EPM) was used for measuring anxiety. Additionally, in order to elucidate whether the new compounds have impact on the central redox balance, we conducted biochemical studies. In doing so, the relative activity of the enzymes responsible for glutathione metabolism – glutathione peroxidase and reductase (GPx and GR) – was measured. The results of the presented studies confirmed the anxiolytic effects of the new compounds 4p (60 mg/kg) and 3o (7.5 mg/kg), and suggested in the mechanism of their action, direct 5‐HT 1A receptors’ participation and indirect involvement of the GABAergic system. Furthermore, the compounds exerted significant agonistic effect with buspirone (BUS, the 5‐HT 1A partial agonist, 1 mg/kg i.p.) and diazepam (DZ, the classic benzodiazepine anxiolytic, 0.25 mg/kg s.c.), while WAY 100635 ( N ‐{2‐[4‐(2‐methoxyphenyl)‐1‐piperazinyl] ethyl}‐ N ‐(2‐pyridyl) cyclohexanecarboxamide, a selective 5‐HT 1A antagonist, 0.1 mg/kg s.c.), but not flumazenil (a GABA A ‐BDZ receptor complex antagonist, 10 mg/kg i.p.) was able to reverse their anxiolytic effects in EPM. A concomitant decrease in GPx by the compound 4p (and to a lesser degree, by compound 3o ) further seemed to confirm their anxiolytic and antioxidant activity.
Knowledge of the metabolic pathways and biotransformation of the most popular drugs, such as cocaine, amphetamine, morphine and others, is crucial for the elucidation of their possible toxicity and mechanism of action in the human body. In vitro studies on metabolism are mainly based on the incubation of drugs with liver cell homogenate and utilizing living animals. These methods need to be followed by isolation and detection of metabolic products, which makes these techniques time-consuming and technically demanding. We show here that the oxidative metabolism that occurs in the liver cells and is mainly caused by cytochrome P450 can be successfully mimicked with the electrochemical system (EC) connected on-line with electrospray ionization mass spectrometry. Cocaine was chosen as a model drug for these studies and was analyzed with a previously described system under various conditions using the boron-doped diamond working electrode. The results were compared with the number of metabolites generated by a standard procedure based on the reaction with the rat liver microsomes. Two electrochemical products of cocaine oxidation were created, of which one was a natural metabolite of cocaine in the human body—norcocaine. The EC provides a promising platform for the screening of the addictive drug phase I metabolism. The metabolites can be directly analyzed by mass spectrometry or collected and separated by liquid chromatography. No liver cell homogenate or microsome is necessary to generate these metabolites, which simplifies separation of the mixtures and reduces time and costs of all experiments.
