Open access journal that offers a platform for the dissemination and
Open access journal that offers a platform for the dissemination and study of clinical, translational and fundamental study findings within this rapidly building field. Improvement in areas such as, but not restricted to, epidemiology, vaccination, hepatitis therapy, pathologySubmit your manuscript here: of Hepatocellular Carcinoma 2021:Powered by TCPDF (www.tcpdf)
Clinical Hemorheology and Microcirculation 79 (2021) 23143 DOI ten.3233/CH-219117 IOS PressInhibition of phase-1 biotransformation and cytostatic effects of diphenyleneiodonium on 15-PGDH Synonyms hepatoblastoma cell line HepG2 and a CYP3A4-overexpressing HepG2 cell cloneChristian Schulza , Friedrich Jungb and Jan-Heiner Kpperb, uFraunhofer Project Group PZ-Syn, Fraunhofer Institute for Cell Therapy and Immunology, Branch Bioanalytics and Bioprocesses (IZI-BB), Potsdam, Germany, situated in the Institute of Biotechnology, Brandenburg University of Technology Cottbus-Senftenberg, Germany b Institute of Biotechnology, Brandenburg University of Technologies Cottbus-Senftenberg, Senftenberg, GermanyaAbstract. Cell-based in vitro liver models are an important tool in the development and evaluation of new drugs in pharmacological and toxicological drug assessment. Hepatic microsomal enzyme complexes, consisting of cytochrome P450 oxidoreductase (CPR) and cytochrome P450 monooxygenases (CYPs), play a decisive role in catalysing phase-1 biotransformation of pharmaceuticals and xenobiotics. To get a comprehensive understanding in the phase-1 biotransformation of drugs, the Necroptosis Synonyms availability of well-characterized substances for the targeted modulation of in vitro liver models is crucial. In this study, we investigated diphenyleneiodonium (DPI) for its capability to inhibit phase-1 enzyme activity and further its toxicological profile in an in vitro HepG2 cell model with and with out recombinant expression in the most important drug metabolization enzyme CYP3A4. Aim with the study was to identify effective DPI concentrations for CPR/CYP activity modulation and potentially connected dose and time dependent hepatotoxic effects. The cells had been treated with DPI doses up to 5,000 nM (versus automobile handle) for any maximum of 48 h and subsequently examined for CYP3A4 activity also as numerous toxicological relevant parameters like cell morphology, integrity and viability, intracellular ATP level, and proliferation. Concluding, the experiments revealed a time- and concentration-dependent DPI mediated partial and complete inhibition of CYP3A4 activity in CYP3A4 overexpressing HepG2-cells (HepG2-CYP3A4). Other cell functions, such as ATP synthesis and consequently the proliferation have been negatively affected in both in vitro cell models. Considering that neither cell integrity nor cell viability were reduced, the effect of DPI in HepG2 may be assessed as cytostatic instead of cytotoxic. Keywords: Phase-1, biotransformation, CYP, cytochrome P450 monooxygenase, CYP3A4, diphenyleneiodonium, DPI, HepG2, HepG2-CYP3A4, hepatocytes, NADPH-cytochrome P450 oxidoreductase, POR, CPR1. Introduction In humans, the liver would be the main organ for the metabolization and elimination of pharmaceuticals and xenobiotics resulting from the higher expression of phase-1 and -2 enzymes in hepatocytes [1]. For this reason, hepatocytes are the topic of intensive study efforts, and in vitro systems based on these cells areCorresponding author: Jan-Heiner Kpper, Institute of Biotechnology, Brandenburg.