50-47-5Relevant articles and documents
Chip-Based P450 Drug Metabolism Coupled to Electrospray Ionization-Mass Spectrometry Detection
Benetton, Salete,Kameoka, Jun,Tan, Aimin,Wachs, Timothy,Craighead, Harold,Henion, Jack D.
, p. 6430 - 6436 (2003)
A chip-based P450 in vitro metabolism assay coupled with ESI-MS and ESI-MS/MS detection is described in this paper. The chips were made of a cyclic olefin polymer using a hot embossing process. The introduction of reagent solutions into the chip was carried out using fused-silica capillaries coupled to two syringes with the flow rate controlled by a syringe pump. Initial experiments described here employed a small commercial guard column in an off-chip format to desalt and concentrate the products of the enzymatic reaction prior to ESI-MS analysis. The system was used both to yield the Michaelis constant (Km) of the P450 biotransformation of imipramine into desipramine and to determine the IC50 value of a chemical inhibitor (tranylcypromine) for this CYP2C19-mediated reaction. The results demonstrated that the kinetics of the reaction inside the 4-μL volume within the channels of the cyclic olefin polymer chip provided results in agreement with those reported in the literature using conventional assays. The above reactions were carried out using human liver microsomes, and the metabolites were detected by ESI-MS showing the potential of the chip-based P450 reaction for metabolite screening studies as well as for P450 inhibition assays. A porous monolithic column was subsequently integrated into the chip to perform the reaction mixture cleanup process in an integrated fashion on the chip that is necessary for ESI-MS detection. The miniature monolithic SPE column was prepared in situ inside the chip via UV-initiated polymerization. The results obtained using the integrated system demonstrated the possibility of performing P450 enzymatic reactions in a microvolume reaction chamber coupled directly to ESI-MS detection and required less than 4 μg of HLM protein.
Bacterial Biosynthetic P450 Enzyme PikCD50N: A Potential Biocatalyst for the Preparation of Human Drug Metabolites
Cheng, Fangyuan,Du, Lei,Durairaj, Pradeepraj,Guo, Jiawei,Li, Fengwei,Li, Shengying,Liu, Xiaohui,Long, Xiangtian,Ma, Li,Tang, Dandan,Zhang, Gang,Zhang, Wei,Zhang, Xingwang
, p. 14563 - 14571 (2021/11/12)
Human drug metabolites (HDMs) are important chemicals widely used in drug-related studies. However, acquiring these enzyme-derived and regio-/stereo-selectively modified compounds through chemical approaches is complicated. PikC is a biosynthetic P450 enz
A Focused Library of Psychotropic Analogues with Neuroprotective and Neuroregenerative Potential
Uliassi, Elisa,Pena-Altamira, Luis Emiliano,Morales, Aixa V.,Massenzio, Francesca,Petralla, Sabrina,Rossi, Michele,Roberti, Marinella,Martinez Gonzalez, Loreto,Martinez, Ana,Monti, Barbara,Bolognesi, Maria Laura
, p. 279 - 294 (2018/10/20)
Overcoming the lack of effective treatments and the continuous clinical trial failures in neurodegenerative drug discovery might require a shift from the prevailing paradigm targeting pathogenesis to the one targeting simultaneously neuroprotection and neuroregeneration. In the studies reported herein, we sought to identify small molecules that might exert neuroprotective and neuroregenerative potential as tools against neurodegenerative diseases. In doing so, we started from the reported neuroprotective/neuroregenerative mechanisms of psychotropic drugs featuring a tricyclic alkylamine scaffold. Thus, we designed a focused-chemical library of 36 entries aimed at exploring the structural requirements for efficient neuroprotective/neuroregenerative cellular activity, without the manifestation of toxicity. To this aim, we developed a synthetic protocol, which overcame the limited applicability of previously reported procedures. Next, we evaluated the synthesized compounds through a phenotypic screening pipeline, based on primary neuronal systems. Phenothiazine 2Bc showed improved neuroregenerative and neuroprotective properties with respect to reference drug desipramine (2Aa). Importantly, we have also shown that 2Bc outperformed currently available drugs in cell models of Alzheimer's and Parkinson's diseases and attenuates microglial activation by reducing iNOS expression.
The use of in vitro data and physiologically-based pharmacokinetic modeling to predict drug metabolite exposure: Desipramine exposure in cytochrome p4502d6 extensive and poor metabolizers following administration of imipramine
Nguyen, Hoa Q.,Callegari, Ernesto,Obach, R. Scott
, p. 1569 - 1578 (2016/10/11)
Major circulating drug metabolites can be as important as the drugs themselves in efficacy and safety, so establishing methods whereby exposure to major metabolites following administration of parent drug can be predicted is important. In this study, imipramine, a tricyclic antidepressant, and itsmajor metabolite desipramine were selected as a model system to develop metabolite prediction methods. Imipramine undergoes N-demethylation to form the activemetabolite desipramine, and both imipramine and desipramine are converted to hydroxylated metabolites by the polymorphic enzyme CYP2D6. The objective of the present study is to determine whether the human pharmacokinetics of desipramine following dosing of imipramine can be predicted using static and dynamic physiologically-based pharmacokinetic (PBPK) models from in vitro input data for CYP2D6 extensive metabolizer (EM) and poor metabolizer (PM) populations. The intrinsic metabolic clearances of parent drug andmetabolite were estimated using human liver microsomes (CYP2D6 PM and EM) and hepatocytes. Passive diffusion clearance of desipramine, used in the estimation of availability of the metabolite, was predicted from passive permeability and hepatocyte surface area. The predicted area under the curve (AUCm/AUCp) of desipramine/imipramine was 12- to 20-fold higher in PM compared with EM subjects following i.v. or oral doses of imipramine using the static model. Moreover, the PBPK model was able to recover simultaneously plasma profiles of imipramine and desipramine in populations with different phenotypes of CYP2D6. This example suggested that mechanistic PBPK modeling combined with information obtained from in vitro studies can provide quantitative solutions to predict in vivo pharmacokinetics of drugs and major metabolites in a target human population.
