@misc{RoselliniSchulzeOmeretal., author = {Rosellini, Matteo and Schulze, Alicia and Omer, Ejlal A. and Ali, Nadeen T. and Marini, Federico and K{\"u}pper, Jan-Heiner and Efferth, Thomas}, title = {The effect of plastic-related compounds on transcriptome-wide gene expression on CYP2C19-overexpressing HepG2 cells}, series = {Molecules}, volume = {28}, journal = {Molecules}, number = {16}, issn = {1420-3049}, doi = {10.3390/molecules28165952}, abstract = {In recent years, plastic and especially microplastic in the oceans have caused huge problems to marine flora and fauna. Recently, such particles have also been detected in blood, breast milk, and placenta, underlining their ability to enter the human body, presumably via the food chain and other yet-unknown mechanisms. In addition, plastic contains plasticizers, antioxidants, or lubricants, whose impact on human health is also under investigation. At the cellular level, the most important enzymes involved in the metabolism of xenobiotic compounds are the cytochrome P450 monooxygenases (CYPs). Despite their extensive characterization in the maintenance of cellular balance, their interactions with plastic and related products are unexplored. In this study, the possible interactions between several plastic-related compounds and one of the most important cytochromes, CYP2C19, were analyzed. By applying virtual compound screening and molecular docking to more than 1000 commercially available plastic-related compounds, we identified candidates that are likely to interact with this protein. A growth inhibition assay confirmed their cytotoxic activity on a CYP2C19-transfected hepatic cell line. Subsequently, we studied the effect of the selected compounds on the transcriptome-wide gene expression level by conducting RNA sequencing. Three candidate molecules were identified, i.e., 2,2′-methylene bis(6-tert-butyl-4-methylphenol), 1,1-bis(3,5-di-tert-butyl-2-hydroxyphenyl) ethane, and 2,2′-methylene bis(6-cyclohexyl-4-methylphenol)), which bound with a high affinity to CYP2C19 in silico. They exerted a profound cytotoxicity in vitro and interacted with several metabolic pathways, of which the 'cholesterol biosynthesis process' was the most affected. In addition, other affected pathways involved mitosis, DNA replication, and inflammation, suggesting an increase in hepatotoxicity. These results indicate that plastic-related compounds could damage the liver by affecting several molecular pathways.}, language = {en} } @misc{ScheibnerKuepperSchmidtkeetal., author = {Scheibner, Katrin and K{\"u}pper, Jan-Heiner and Schmidtke, Kai-Uwe and Miethbauer, Sebastian and Herzog, Natalie}, title = {Verfahren zur Herstellung von biogenen Stoffen}, language = {de} } @misc{ScheibnerKiebistSchmidtkeetal., author = {Scheibner, Katrin and Kiebist, Jan and Schmidtke, Kai-Uwe and K{\"u}pper, Jan-Heiner}, title = {Verfahren zur enzymatischen Herstellung von zytostatischen 4-Hydroxy-Oxazaphosphorinen"}, language = {de} } @misc{ScheibnerKuepperJung, author = {Scheibner, Katrin and K{\"u}pper, Jan-Heiner and Jung, Friedrich}, title = {In vitro Arzneimittel aus Prodrugs und deren Verwendung}, language = {de} } @misc{BuchmuellerEngePetersetal., author = {Buchmueller, Julia and Enge, Anne-Margarethe and Peters, Antonia and Ebmeyer, Johanna and K{\"u}pper, Jan-Heiner and Sch{\"a}fer, Bernd and Br{\"a}uning, Albert and Hessel-Pras, Stefanie}, title = {The chemical structure impairs the intensity of genotoxic effects promoted by 1,2-unsaturated pyrrolizidine alkaloids in vitro}, series = {Food and Chemical Toxicology}, volume = {Vol. 164}, journal = {Food and Chemical Toxicology}, issn = {1873-6351}, doi = {10.1016/j.fct.2022.113049}, language = {en} } @misc{AbdelfatahNassKnorzetal., author = {Abdelfatah, Sara and Nass, Janine and Knorz, Caroline and Klauck, Sabine M. and K{\"u}pper, Jan-Heiner and Efferth, Thomas}, title = {Pyrrolizidine alkaloids cause cell cycle and DNA damage repair defects as analyzed by transcriptomics in cytochrome P450 3A4-overexpressing HepG2 clone 9 cells}, series = {Cell biology and toxicology}, volume = {38}, journal = {Cell biology and toxicology}, number = {2}, issn = {1573-6822}, doi = {10.1007/s10565-021-09599-9}, pages = {325 -- 345}, language = {en} } @misc{GeburekRutzGaoetal., author = {Geburek, Ina and Rutz, Lukas and Gao, Lan and K{\"u}pper, Jan-Heiner and These, Anja and Schrenk, Dieter}, title = {The metabolic pattern of hepatotoxic pyrrolizidine alkaloids in liver cells}, series = {Chemical Research in Toxicology}, volume = {34}, journal = {Chemical Research in Toxicology}, number = {4}, doi = {10.1021/acs.chemrestox.0c00507}, pages = {1101 -- 1113}, abstract = {Contamination with 1,2-unsaturated pyrrolizidine alkaloids (PAs) is a serious problem for certain phytomedicines, foods, and animal feeds. Several of these PAs are genotoxic and carcinogenic, primarily in the liver, upon cytochrome P450 (CYP)-catalyzed activation into reactive (pyrrolic and pyrrole-like) metabolites. Here we investigated the metabolism of selected PAs (echimidine, europine, lasiocarpine, lycopsamine, retrorsine, and senecionine) in rat hepatocytes in primary culture and in human CYP3A4-transfected HepG2 cells. The open-chained diesters echimidine and lasiocarpine and the cyclic diester senecionine were extensively metabolized in rat hepatocytes into a broad spectrum of products released into the medium. A large portion of unidentified, possibly irreversibly bound, products remained in the cells while detectable amounts of reactive and other metabolites were found in the incubation media. In HepG2-CYP3A4 cells, lasiocarpine was more extensively metabolized than echimidine and senecionine which also gave rise to the release of pyrrolic metabolites. In human cells, no pyrrolic metabolites were detected in retrorsine or lycopsamine incubations, while no such metabolites were detected from europine in both cell types. Other types of metabolic changes comprised modifications such as side chain demethylation or oxygenation reactions like the formation of N-oxides. The latter, considered as a detoxification step, was a major pathway with cyclic diesters, was less distinctive for echimidine and lycopsamine and almost negligible for lasiocarpine and europine. Our data are in agreement with previously published cyto- and genotoxicity findings and suggests that the metabolic pattern may contribute substantially to the specific toxic potency of a certain congener. In addition, marked differences were found for certain congeners between rat hepatocytes and transfected human HepG2 cells, whereby a high level of bioactivation was found for lasiocarpine, whereas a very low level of bioactivation was observed for monoesters, in particular in human cells.}, language = {en} } @misc{JungWaldeckPetricketal., author = {Jung, Conrad H. G. and Waldeck, Peter and Petrick, Ingolf and Braune, Steffen and K{\"u}pper, Jan-Heiner and Jung, Friedrich}, title = {Bioreactor for the cultivation of Arthrospira platensis under controlled conditions}, series = {Journal of Cellular Biotechnology}, volume = {7}, journal = {Journal of Cellular Biotechnology}, number = {1}, doi = {10.3233/JCB-210032}, pages = {35 -- 40}, abstract = {A vertical flat-type bioreactor consisting of transparent polyethylene (food safe) was constructed, which is characterized by a flexible design and allows the adjustment of a light path of 1 cm - 8.5 cm and a working volume of 1.5 l - 4 l. To characterize the performance of the bioreactor, cultivation experiments were performed with the cyanobacterium Arthrospira platensis (AP). The growth was assessed continuously by monitoring optical density and intermittently by measuring the dry weight of the AP biomass. An on-line measurement technique for estimating biomass production rate in a photosynthetic microalgae culture was developed. The oxygen produced by AP in the culture medium was flushed out sparging using a mixture of air and CO2 (1\%). Factors which might influence the AP growth were monitored: pH, temperature, oxygen concentration and the filling level were corrected automatically to compensate evaporation losses. As an example, the huge influence of the light intensity on the AP growth was tested. The increase of the photon flux density of 15 to 1200μmol/(l · d) led to a 22-fold increase of the productivity and a 3.1-fold shorter doubling time. Using an online measurement technique - together with the control of the growth process via a wireless local area network (WLAN) router and virtual private network - allows monitoring the growth of Arthrospira platensis remotely.}, language = {en} } @misc{BrauneKruegerGengeKammereretal., author = {Braune, Steffen and Kr{\"u}ger-Genge, Anne and Kammerer, Sarah and Jung, Friedrich and K{\"u}pper, Jan-Heiner}, title = {Phycocyanin from Arthrospira platensis as Potential Anti-Cancer Drug: Review of In Vitro and In Vivo Studies}, series = {Life}, volume = {11}, journal = {Life}, number = {2}, doi = {10.3390/life11020091}, pages = {91}, language = {en} } @misc{SchulzJungKuepper, author = {Schulz, Christian and Jung, Friedrich and K{\"u}pper, Jan-Heiner}, title = {Inhibition of phase-1 biotransformation and cytostatic effects of diphenyleneiodonium on hepatoblastoma cell line HepG2 and a CYP3A4-overexpressing HepG2 cell clone}, series = {Clinical Hemorheology and Microcirculation}, volume = {79}, journal = {Clinical Hemorheology and Microcirculation}, number = {1}, issn = {1875-8622}, doi = {10.3233/CH-219117}, pages = {231 -- 243}, abstract = {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. For a comprehensive understanding of the phase-1 biotransformation of drugs, the availability of well-characterized substances for the targeted modulation of in vitro liver models is essential. In this study, we investigated diphenyleneiodonium (DPI) for its ability to inhibit phase-1 enzyme activity and further its toxicological profile in an in vitro HepG2 cell model with and without recombinant expression of the most important drug metabolization enzyme CYP3A4. Aim of the study was to identify effective DPI concentrations for CPR/CYP activity modulation and potentially associated dose and time dependent hepatotoxic effects. The cells were treated with DPI doses up to 5,000nM (versus vehicle control) for a maximum of 48 h and subsequently examined for CYP3A4 activity as well as various toxicological relevant parameters such as 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, including ATP synthesis and consequently the proliferation were negatively affected in both in vitro cell models. Since neither cell integrity nor cell viability were reduced, the effect of DPI in HepG2 can be assessed as cytostatic rather than cytotoxic.}, language = {en} }