TY - GEN A1 - Herzog, Natalie A1 - Hansen, Max A1 - Miethbauer, Sebastian A1 - Schmidtke, Kai-Uwe A1 - Anderer, Ursula A1 - Lupp, Amelie A1 - Sperling, Sebastian A1 - Seehofer, Daniel A1 - Damm, Georg A1 - Scheibner, Katrin A1 - Küpper, Jan-Heiner T1 - Primary-like human hepatocytes genetically engineered to obtain proliferation competence display hepatic differentiation characteristics in monolayer and organotypical spheroid cultures T2 - Cell Biology International N2 - Primary human hepatocytes are in great demand during drug development and in hepatology. However, both scarcity of tissue supply and donor variability of primary cells create a need for the development of alternative hepatocyte systems. By using a lentivirus vector system to transfer coding sequences of Upcyte® proliferation genes, we generated non-transformed stable hepatocyte cultures from human liver tissue samples. Here, we show data on newly generated proliferation-competent HepaFH3 cells investigated as conventional two-dimensional monolayer and as organotypical three-dimensional (3D) spheroid culture. In monolayer culture, HepaFH3 cells show typical cobblestone-like hepatocyte morphology and anchorage-dependent growth for at least 20 passages. Immunofluorescence staining revealed that characteristic hepatocyte marker proteins cytokeratin 8, human serum albumin, and cytochrome P450 (CYP) 3A4 were expressed. Quantitative real-time PCR analyses showed that expression levels of analyzed phase I CYP enzymes were at similar levels compared to those of cultured primary human hepatocytes and considerably higher than in the liver carcinoma cell line HepG2. Additionally, transcripts for phase II liver enzymes and transporter proteins OATP-C, MRP2, Oct1, and BSEP were present in HepaFH3. The cells produced urea and converted model compounds such as testosterone, diclofenac, and 7-OH-coumarin into phases I and II metabolites. Interestingly, phases I and II enzymes were expressed at about the same levels in convenient monolayer cultures and complex 3D spheroids. In conclusion, HepaFH3 cells and related primary-like hepatocyte lines seem to be promising tools for in vitro research of liver functions and as test system in drug development and toxicology analysis. KW - cytochrome P450 enzyme Y1 - 2016 UR - http://onlinelibrary.wiley.com/doi/10.1002/cbin.10574/full U6 - https://doi.org/10.1002/cbin.10574 SN - 1095-8355 VL - 40 IS - 3 SP - 341 EP - 353 ER - TY - GEN A1 - Kade, S. A1 - Herzog, Natalie A1 - Schmidtke, Kai-Uwe A1 - Küpper, Jan-Heiner T1 - Chronic ethanol treatment depletes glutathione regeneration capacity in hepatoma cell line HepG2 T2 - Journal of Cellular Biotechnology Y1 - 2016 U6 - https://doi.org/10.3233/JCB-15019 SN - 2352-3697 SN - 2352-3689 VL - 1 IS - 2 SP - 183 EP - 190 ER - TY - GEN A1 - Herzog, Natalie A1 - Hansen, Max A1 - Miethbauer, Sebastian A1 - Schmidtke, Kai-Uwe A1 - Anderer, Ursula A1 - Lupp, Amelie A1 - Sperling, Sebastian A1 - Seehofer, Daniel A1 - Damm, Georg A1 - Scheibner, Katrin A1 - Küpper, Jan-Heiner T1 - Primary like human hepatocytes genetically engineered to obtain proliferation competence display liver biotransformation activity in 2D and 3D culture systems T2 - Cell Biology International Y1 - 2016 SN - 1095-8355 SN - 1065-6995 VL - 40 IS - 3 SP - 341 EP - 353 ER - TY - GEN A1 - George, Sandra A1 - Rödiger, Stefan A1 - Schröder, Christian A1 - Knaut, Michael A1 - Küpper, Jan-Heiner T1 - Development of multiplex PCR systems for expression profiling of human cardiomyocytes induced to profilerate by lentivirus transduction of upcyte genes T2 - Journal of Cellular Biotechnology Y1 - 2016 U6 - https://doi.org/10.3233/JCB-15025 SN - 2352-3697 SN - 2352-3689 VL - 2 IS - 1 SP - 35 EP - 55 ER - TY - GEN A1 - Meyer, Ralph G. A1 - Meyer-Ficca, Mirella A1 - Küpper, Jan-Heiner T1 - Adenoviral vectors for modulation of poly(ADP-ribose) polymerase-1 (PARP1) - dependent DNA repair as a predictive tool for chemotherapy T2 - Journal of Cellular Biotechnology Y1 - 2016 U6 - https://doi.org/10.3233/JCB-15026 SN - 2352-3697 SN - 2352-3689 VL - 2 IS - 1 SP - 57 EP - 68 ER - TY - GEN A1 - Herzog, Natalie A1 - Katzenberger, Nadine A1 - Martin, Frank A1 - Schmidtke, Kai-Uwe A1 - Küpper, Jan-Heiner T1 - Generation of cytochrome P450 3A4-overexpressing HepG2 cell clones for standardization of hepatocellular testosterone 6β-hydroxylation activity T2 - Journal of Cellular Biotechnology Y1 - 2015 U6 - https://doi.org/10.3233/JCB-15002 SN - 2352-3697 SN - 2352-3689 VL - 1 IS - 1 SP - 15 EP - 26 ER - TY - GEN A1 - George, Sandra A1 - Noack, M. A1 - Vanek, Monika A1 - Rentzsch, J. A1 - Röber, Nadja A1 - Roggenbuck, Dirk A1 - Conrad, Karsten A1 - Küpper, Jan-Heiner T1 - Expression of nicotinic acetylcholine receptor subunits in HEp-2 cells for immunodetection of autoantibody specificities in sera fro Myasthenia gravis patients T2 - Clinical Hemorheology and Microcirculation Y1 - 2015 U6 - https://doi.org/10.3233/CH-151999 SN - 1875-8622 SN - 1386-0291 VL - 61 IS - 2 SP - 385 EP - 396 ER - TY - GEN A1 - George, Sandra A1 - Paulick, Silvia A1 - Knütter, Ilka A1 - Röber, Nadja A1 - Hiemann, Rico A1 - Roggenbuck, Dirk A1 - Conrad, Karsten A1 - Küpper, Jan-Heiner T1 - Stable Expression of Human Muscle-Specific Kinase in HEp-2 M4 Cells for Automatic Immunofluorescence Diagnostics of Myasthenia Gravis T2 - PLOS one Y1 - 2014 U6 - https://doi.org/10.1371/journal.pone.0083924 SN - 1932-6203 VL - 9 IS - 1 SP - e83924 ER - TY - GEN A1 - George, Sandra A1 - Georgi, M. A1 - Roggenbuck, Dirk A1 - Conrad, Karsten A1 - Küpper, Jan-Heiner T1 - A strategy for cell-based multiplex diagnostics of Myasthenia gravis and autoimmune encephalitis by modifying the subcellular localization of cell membrane autoantigensgravis T2 - Clinical Hemorheology and Microcirculation Y1 - 2014 U6 - https://doi.org/10.3233/CH-141897 SN - 1386-0291 SN - 1875-8622 VL - 58 IS - 1 SP - 211 EP - 228 ER - TY - CHAP A1 - Conrad, Karsten A1 - Küpper, Jan-Heiner ED - Shoenfeld, Yehuda ED - Meroni, Pier Luigi ED - Gershwin, M. Eric T1 - Tumor-associated autoantibodies T2 - Autoantibodies Y1 - 2014 SN - 978-0-444-56378-1 SN - 978-0-444-59377-1 SP - 275 EP - 287 PB - Elsevier CY - Amsterdam [u.a.] ET - 3rd edition ER - TY - GEN A1 - Nowak, Elisabeth A1 - Martin, F. A1 - George, Sandra A1 - Röber, Nadja A1 - Conrad, Karsten A1 - Küpper, Jan-Heiner T1 - Bacterial production and purification of immunoreactive paraneoplastic neurological syndrome autoantigen Ma2 T2 - Journal of Cellular Biotechnology N2 - Paraneoplastic neurological syndromes (PNS) are caused by an immune response against neuronal proteins upon their ectopical expression in tumor cells. Ma2 belongs to the protein family of paraneoplastic Ma antigens (PNMA). Detection of Ma2-specific autoantibodies is relevant for diagnostics of anti-Ma2 PNS and an underlying tumor such as germ testicular cancer, small cell lung cancer or breast cancer. Thus, early tumor treatment should improve the outcome for PNS therapy either. Dot blot immunoassay based on recombinantly expressed and purified autoantigens could offer a sensitive method for identification of paraneoplastic autoantibodies from sera of PNS patients. Here we present purification with IMAC and FPLC of human Ma2 autoantigen upon its recombinant expression in E.coli. Furthermore, we provide evidence that dot blot immunoassays with purified Ma2 autoantigen can be used for detection of Ma2-specific autoantibodies from sera of PNS patients. KW - Autoimmune disease KW - autoantibodies KW - dot blot immunoassay KW - FPLC KW - IMAC KW - Ma2 KW - PNMA2 KW - PNS KW - T7 expression system Y1 - 2017 UR - https://content.iospress.com/articles/journal-of-cellular-biotechnology/jcb15029 U6 - https://doi.org/10.3233/JCB-15029 SN - 2352-3697 VL - 2 IS - 2 SP - 85 EP - 91 ER - TY - BOOK A1 - Paumen, Anja A1 - Küpper, Jan-Heiner T1 - It’s the planet, stupid! Sieben Perspektiven zum Klimawandel : mit Interviewbeiträgen von Hartmut Graßl, Hans-Werner Sinn, Ernst-Ulrich von Weizsäcker, Meinhard Miegel, Mathias Binswanger, Enoch zu Guttenberg und Wulf Schiefenhövel Y1 - 2015 SN - 978-3-86581-739-6 SN - 3-86581-739-4 PB - oekom Verlag CY - München ER - TY - CHAP A1 - George, Sandra A1 - Noack, Monika A1 - Vanek, Monika A1 - Rentzsch, Juliane A1 - Röber, Nadja A1 - Conrad, Karsten A1 - Roggenbuck, Dirk A1 - Küpper, Jan-Heiner T1 - Expression of nicotinic acetylcholine receptor subunits in HEp-2 cells for immunodetection of autoantibody specificities in sera from Myasthenia gravis patients T2 - From autoantibody research to standardized diagnostic assays in the management of human diseases, report on the 12th Dresden Symposium on Autoantibodies, September 23-26, 2015 Y1 - 2015 SN - 978-3-95853-104-8 SP - 195 EP - 196 PB - Pabst Science Publishers CY - Lengerich ER - TY - GEN A1 - Kammerer, Sarah A1 - Küpper, Jan-Heiner T1 - Human Hepatocyte Systems for in vitro Toxicology Analysis. T2 - Journal of Cellular Biotechnology Y1 - 2018 U6 - https://doi.org/10.3233/JCB-179012 SN - 2352-3697 SN - 2352-3689 VL - 3 IS - 2 SP - 85 EP - 93 ER - TY - GEN A1 - Haileka, Vanessa A1 - George, Sandra A1 - Steinbrecht, Susanne A1 - Jung, Friedrich A1 - Reinehr, R. A1 - Küpper, Jan-Heiner T1 - Colon cancer cells cultured under hyperosmotic conditions as in vitro model to investigate dehydration effects on cancer drug susceptibility T2 - Clinical Hemorheology and Microcirculation Y1 - 2019 U6 - https://doi.org/10.3233/CH-199210 SN - 1875-8622 VL - 73 IS - 1 SP - 169 EP - 176 ER - TY - GEN A1 - Schulte-Hubbert, Ruth A1 - Küpper, Jan-Heiner A1 - Thomas, Adam D. A1 - Schrenk, Dieter T1 - Estragole: DNA adduct formation in primary rat hepatocytes and genotoxic potential in HepG2-CYP1A2 cells T2 - Toxicology N2 - Estragole is a natural constituent in herbs and spices and in products thereof such as essential oils or herbal teas. After cytochrome P450-catalyzed hydroxylation and subsequent sulfation, estragole acts as a genotoxic hepatocarcinogen forming DNA adducts in rodent liver. Because of the genotoxic mode of action and the widespread occurrence in food and phytomedicines a refined risk assessment for estragole is needed. We analyzed the time- and concentration-dependent levels of the DNA adducts N2-(isoestragole-3‘-yl)-2‘-desoxyguanosine (E3′N2dG) and N6-(isoestragole-3‘-yl)-desoxyadenosine (E3′N6dA), reported to be the major adducts formed in rat liver, in rat hepatocytes (pRH) in primary culture after incubation with estragole. DNA adduct levels were measured via UHPLC-ESI-MS/MS using stable isotope dilution analysis. Both adducts were formed in pRH and could already be quantified after an incubation time of 1 h (E3′N6dA at 10 μM, E3′N2dG at 1μM estragole). E3′N2dG, the main adduct at all incubation times and concentrations, could be detected at estragole concentrations < 0.1 μM after 24 h and < 0.5 μM after 48 h. Adduct levels were highest after 6 h and showed a downward trend at later time-points, possibly due to DNA repair and/or apoptosis. While the concentration-response characteristics of adduct formation were apparently linear over the whole concentration range, strong indication for marked hypo-linearity was obtained when the modeling was based on concentrations < 1 μM only. In the micronucleus assay no mutagenic potential of estragole was found in HepG2 cells whereas in HepG2-CYP1A2 cells 1 μM estragole led to a 3.2 fold and 300 μM to a 7.1 fold increase in micronuclei counts. Our findings suggest the existence of a ‘practical threshold’ dose for DNA adduct formation as an initiating key event of the carcinogenicity of estragole indicating that the default assumption of concentration-response-linearity is questionable, at least for the two major adducts studied here. KW - Estragole KW - Carcinogenicity KW - DNA adducts KW - Genotoxicity KW - Hepatoma KW - Liver cells Y1 - 2020 UR - https://www.sciencedirect.com/science/article/pii/S0300483X20302055 U6 - https://doi.org/10.1016/j.tox.2020.152566 SN - 0300-483X VL - 444 ER - TY - GEN A1 - Rutz, Lukas A1 - Gao, Lan A1 - Küpper, Jan-Heiner A1 - Schrenk, Dieter T1 - Structure-dependent genotoxic potencies of selected pyrrolizidine alkaloids in metabolically competent HepG2 cells T2 - Archives of Toxicology N2 - 1,2-unsaturated pyrrolizidine alkaloids (PAs) are natural plant constituents comprising more than 600 different structures. A major source of human exposure is thought to be cross-contamination of food, feed and phytomedicines with PA plants. In humans, laboratory and farm animals, certain PAs exert pronounced liver toxicity and can induce malignant liver tumors in rodents. Here, we investigated the cytotoxicity and genotoxicity of eleven PAs belonging to different structural classes. Although all PAs were negative in the fluctuation Ames test in Salmonella, they were cytotoxic and induced micronuclei in human HepG2 hepatoblastoma cells over-expressing human cytochrome P450 3A4. Lasiocarpine and cyclic diesters except monocrotaline were the most potent congeners both in cytotoxicity and micronucleus assays with concentrations below 3 μM inducing a doubling in micronuclei counts. Other open di-esters and all monoesters exhibited weaker or much weaker geno- and cytotoxicity. The findings were in agreement with recently suggested interim Relative Potency (iREP) factors with the exceptions of europine and monocrotaline. A more detailed micronuclei analysis at low concentrations of lasiocarpine, retrorsine or senecionine indicated that pronounced hypolinearity of the concentration–response curves was evident for retrorsine and senecionine but not for lasiocarpine. Our findings show that the genotoxic and cytotoxic potencies of PAs in a human hepatic cell line vary in a structure-dependent manner. Both the low potency of monoesters and the shape of prototype concentration–response relationships warrant a substance- and structure-specific approach in the risk assessment of PAs. KW - Genotoxicity KW - Liver cells KW - Micronuclei KW - Mutagenicity KW - Pyrrolizidine alkaloids KW - Relative potencies Y1 - 2020 UR - https://link.springer.com/article/10.1007/s00204-020-02895-z U6 - https://doi.org/10.1007/s00204-020-02895-z SN - 0340-5761 SN - 1432-0738 VL - 94 IS - 12 SP - 4159 EP - 4172 ER - TY - GEN A1 - Künzel, Stephan R. A1 - Rausch, Johanna S. E. A1 - Schäffer, Charlotte A1 - Hoffmann, Maximilian A1 - Künzel, Karolina A1 - Klapproth, Erik A1 - Kant, Theresa A1 - Herzog, Natalie A1 - Küpper, Jan-Heiner A1 - Lorenz, Kristina A1 - Dudek, Svenja A1 - Emig, Ramona A1 - Ravens, Ursula A1 - Rog‐Zielinska, Eva A. A1 - Peyronnet, Rémi A1 - El‐Armouche, Ali T1 - Modeling atrial fibrosis in vitro - Generation and characterization of a novel human atrial fibroblast cell line T2 - FEBS Open Bio N2 - Atrial fibrillation (AF) is regularly accompanied by cardiac fibrosis and concomitant heart failure. Due to the heterogeneous nature and complexity of fibrosis, the knowledge about the underlying mechanisms is limited, which prevents effective pharmacotherapy. A deeper understanding of cardiac fibroblasts is essential to meet this need. We previously described phenotypic and functional differences between atrial fibroblasts from patients in sinus rhythm and with AF. Herein, we established and characterized a novel human atrial fibroblast line, which displays typical fibroblast morphology and function comparable to primary cells but with improved proliferation capacity and low spontaneous myofibroblast differentiation. These traits make our model suitable for the study of fibrosis mechanisms and for drug screening aimed at developing effective antifibrotic pharmacotherapy. KW - cardiovascular disease KW - cell culture KW - cell lines KW - fibroblasts KW - fibrosis KW - heart Y1 - 2020 U6 - https://doi.org/10.1002/2211-5463.12896 SN - 2211-5463 VL - 10 IS - 7 SP - 1210 EP - 1218 ER - TY - GEN A1 - Jung, Friedrich A1 - Krüger-Genge, Anne A1 - Franke, Ralf-Peter A1 - Hufert, Frank A1 - Küpper, Jan-Heiner T1 - COVID-19 and the endothelium T2 - Clinical Hemorheology and Microcirculation N2 - There is growing evidence that COVID-19 not only affects the lungs but beyond that the endothelial system. Recent studies showed that this can lead to microcirculatory impairments and in consequence to functional disorders of all inner organs. The combination of endothelial dysfunction with a generalized inflammatory state and complement elements may together contribute to the overall pro-coagulative state described in COVID-19 patients leading to venular as well as to arteriolar occlusions. KW - COVID-19 KW - endocytosis KW - endothelial cell dysfunction KW - endotheliitis Y1 - 2020 UR - https://content.iospress.com/articles/clinical-hemorheology-and-microcirculation/ch209007 U6 - https://doi.org/10.3233/CH-209007 SN - 1875-8622 SN - 1386-0291 VL - 75 IS - 1 SP - 7 EP - 11 ER - TY - GEN A1 - Jung, Friedrich A1 - Krieger, Volker A1 - Hufert, Frank A1 - Küpper, Jan-Heiner T1 - Herd immunity or suppression strategy to combat COVID-19 T2 - Clinical Hemorheology and Microcirculation N2 - Some months ago, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) broke out in Wuhan, China, and spread rapidly around the world. Some states, such as the Netherlands, Germany, Great Britain, Sweden and the USA initially focused on keeping the restrictions for economy and society as low as possible. The responsible authorities were of the opinion - and still are e.g. in Sweden - that it is sufficient enough to protect particularly vulnerable persons such as the elderly or people with pre-existing conditions. The idea behind this is that as soon as 60 to 70 percent of the population is infected with a pathogen, a so-called “herd immunity” has developed. However, the increasing numbers of deaths and modelling studies showed the expected overload of the hospitals. Therefore, most countries decided for a temporary lockdown with the exception of Sweden. Based on the number of the total population, three times more people died from COVID-19 in Sweden (2679 deaths per 10 million inhabitants) compared to Germany (6848 deaths per 80 million inhabitants). The comparison Sweden versus Taiwan is even worse because 1072 times more people died in Sweden based on the number of the population (6 deaths per 24 million inhabitants). KW - COVID-19 KW - strategy KW - Sweden KW - Taiwan KW - Germany Y1 - 2020 UR - https://content.iospress.com/articles/clinical-hemorheology-and-microcirculation/ch209006 U6 - https://doi.org/10.3233/CH-209006 SN - 1875-8622 SN - 1386-0291 VL - 75 IS - 1 SP - 13 EP - 17 ER - TY - GEN A1 - Steinbrecht, Susanne A1 - Kiebist, Jan A1 - König, Rosalie A1 - Thiessen, Markus A1 - Schmidtke, Kai-Uwe A1 - Kammerer, Sarah A1 - Küpper, Jan-Heiner A1 - Scheibner, Katrin T1 - Synthesis of cyclophosphamide metabolites by a peroxygenase from Marasmius rotula for toxicological studies on human cancer cells T2 - AMB Express N2 - Cyclophosphamide (CPA) represents a widely used anti-cancer prodrug that is converted by liver cytochrome P450 (CYP) enzymes into the primary metabolite 4-hydroxycyclophosphamide (4-OH-CPA), followed by non-enzymatic generation of the bioactive metabolites phosphoramide mustard and acrolein. The use of human drug metabolites as authentic standards to evaluate their toxicity is essential for drug development. However, the chemical synthesis of 4-OH-CPA is complex and leads to only low yields and undesired side products. In past years, fungal unspecific peroxygenases (UPOs) have raised to powerful biocatalysts. They can exert the identical selective oxyfunctionalization of organic compounds and drugs as known for CYP enzymes with hydrogen peroxide being used as sole cosubstrate. Herein, we report the efficient enzymatic hydroxylation of CPA using the unspecific peroxygenase from Marasmius rotula (MroUPO) in a simple reaction design. Depending on the conditions used the primary liver metabolite 4-OH-CPA, its tautomer aldophosphamide (APA) and the overoxidized product 4-ketocyclophosphamide (4-keto-CPA) could be obtained. Using a kinetically controlled approach 4-OH-CPA was isolated with a yield of 32% (purity > 97.6%). Two human cancer cell lines (HepG2 and MCF-7) were treated with purified 4-OH-CPA produced by MroUPO (4-OH-CPAUPO). 4-OH-CPAUPO–induced cytotoxicity as measured by a luminescent cell viability assay and its genotoxicity as measured by γH2AX foci formation was not significantly different to the commercially available standard. The high yield of 4-OH-CPAUPO and its biological activity demonstrate that UPOs can be efficiently used to produce CYP-specific drug metabolites for pharmacological assessment. KW - Biocatalysis KW - Cyclophosphamide KW - Human drug metabolites KW - Peroxygenase KW - Toxicity Y1 - 2020 UR - https://amb-express.springeropen.com/articles/10.1186/s13568-020-01064-w U6 - https://doi.org/10.1186/s13568-020-01064-w SN - 2191-0855 VL - 10 ER - TY - GEN A1 - Lau, S. A1 - Rangarajan, R. A1 - Krüger-Genge, Anne A1 - Braune, Steffen A1 - Küpper, Jan-Heiner A1 - Lendlein, Andreas A1 - Jung, Friedrich T1 - Age-related morphology and function of human arterial endothelial cells T2 - Clinical Hemorheology and Microcirculation N2 - Endothelialization of cardiovascular implants is regarded as a promising strategy for long-term compatibility. While umbilical vein endothelial cells are typically applied in research, human arterial endothelial cells (HAEC) from elderly donors would be the obvious source for autologous cellularization strategies. In our approach, HAEC from 16 donors of varying age (16–63 years) were divided into two groups (<30 years and >30 years) and analyzed regarding morphology, viability, proliferation, function and senescence status. No age-related differences were found regarding morphology, viability, density, prostacyclin and nitrite secretion or collagen and laminin production. However, the metabolic activity was slightly decreased (p = 0.0374) and the membrane integrity marginally impaired (p = 0.0404) in cells from older donors. Two out of three senescence assays detected more senescence markers in cells from older donors. According to the assays applied here, HAEC from young and elderly donors up to the age of 63 years could be judged equally suitable for autologous cellularization strategies. However, this finding should be regarded with caution due to the extremely large variability between individual donors. Further studies comprising a larger sample size are necessary to investigate this issue more thoroughly. KW - Cardiovascular implants KW - arterial endothelial cells KW - aging KW - senescence KW - donor variability Y1 - 2020 UR - https://content.iospress.com/articles/clinical-hemorheology-and-microcirculation/ch199238 U6 - https://doi.org/10.3233/CH-199238 SN - 1875-8622 SN - 1386-0291 VL - 74 IS - 1 SP - 93 EP - 107 ER - TY - GEN A1 - Krüger-Genge, Anne A1 - Steinbrecht, Susanne A1 - Jung, Conrad H. G. A1 - Westphal, Sophia A1 - Klöpzig, Stefanie A1 - Waldeck, Peter A1 - Küpper, Jan-Heiner A1 - Storsberg, J. A1 - Jung, Friedrich T1 - Arthrospira platensis accelerates the formation of an endothelial cell monolayer and protects against endothelial cell detachment after bacterial contamination T2 - Clinical Hemorheology and Microcirculation N2 - Within the last years a comprehensive number of scientific studies demonstrated beneficial effect of Arthropira platensis (AP) as dietary supplement due to a high content of proteins, minerals and vitamins. Positive effects like promoting the immune system, reducing inflammation and an anti-oxidant capacity are reported. In this study, the effect of an aqueous AP extract on primary human venous endothelial cells (HUVEC) was investigated. In addition, the effect of AP on HUVEC treated with a bacterial toxin (lipopolysaccharide, LPA), inducing an activation of HUVEC and cellular detachment, was analyzed. Depending on the concentration of AP extract a significantly accelerated formation of an endothelial cell monolayer was observed. Furthermore, the detachment of HUVEC after LPA addition was dramatically reduced by AP. In conclusion, the data are promising and indicatory for an application of Arthrospira platensis in the clinical field. KW - Arthrospira platensis KW - endothelial cells KW - xCELLigence system Y1 - 2021 UR - https://content.iospress.com/articles/clinical-hemorheology-and-microcirculation/ch201096 U6 - https://doi.org/10.3233/CH-201096 SN - 1386-0291 VL - 78 IS - 2 SP - 151 EP - 161 ER - TY - GEN A1 - Schulz, Christian A1 - Krüger-Genge, Anne A1 - Lendlein, Andreas A1 - Küpper, Jan-Heiner A1 - Jung, Friedrich T1 - Potential Effects of Nonadherent on Adherent Human Umbilical Venous Endothelial Cells in Cell Culture T2 - International Journal of Molecular Science N2 - The adherence and shear-resistance of human umbilical venous endothelial cells (HUVEC) on polymers is determined in vitro in order to qualify cardiovascular implant materials. In these tests, variable fractions of HUVEC do not adhere to the material but remain suspended in the culture medium. Nonadherent HUVEC usually stop growing, rapidly lose their viability and can release mediators able to influence the growth and function of the adherent HUVEC. The aim of this study was the investigation of the time dependent behaviour of HUVEC under controlled nonadherent conditions, in order to gain insights into potential influences of these cells on their surrounding environment in particular adherent HUVEC in the context of in vitro biofunctionality assessment of cardiovascular implant materials. Data from adherent or nonadherent HUVEC growing on polystyrene-based cell adhesive tissue culture plates (TCP) or nonadhesive low attachment plates (LAP) allow to calculate the number of mediators released into the culture medium either from adherent or nonadherent cells. Thus, the source of the inflammatory mediators can be identified. For nonadherent HUVEC, a time-dependent aggregation without further proliferation was observed. The rate of apoptotic/dead HUVEC progressively increased over 90% within two days. Concomitant with distinct blebbing and loss of membrane integrity over time, augmented releases of prostacyclin (PGI2, up to 2.91 ± 0.62 fg/cell) and platelet-derived growth factor BB (PDGF-BB, up to 1.46 ± 0.42 fg/cell) were detected. The study revealed that nonadherent, dying HUVEC released mediators, which can influence the surrounding microenvironment and thereby the results of in vitro biofunctionality assessment of cardiovascular implant materials. Neglecting nonadherent HUVEC bears the risk for under- or overestimation of the materials endothelialization potential, which could lead to the loss of relevant candidates or to uncertainty with regard to their suitability for cardiac applications. One approach to minimize the influence from nonadherent endothelial cells could be their removal shortly after observing initial cell adhesion. However, this would require an individual adaptation of the study design, depending on the properties of the biomaterial used. KW - human venous endothelial cells KW - adherent KW - non-adherent KW - viability KW - mediator release Y1 - 2021 UR - https://www.mdpi.com/1422-0067/22/3/1493 U6 - https://doi.org/10.3390/ijms22031493 VL - 22 IS - 3 ER - TY - GEN A1 - Braune, Steffen A1 - Küpper, Jan-Heiner A1 - Jung, Friedrich T1 - Effect of Prostanoids on Human Platelet Function: An Overview T2 - International Journal of Molecular Science N2 - Prostanoids are bioactive lipid mediators and take part in many physiological and pathophysiological processes in practically every organ, tissue and cell, including the vascular, renal, gastrointestinal and reproductive systems. In this review, we focus on their influence on platelets, which are key elements in thrombosis and hemostasis. The function of platelets is influenced by mediators in the blood and the vascular wall. Activated platelets aggregate and release bioactive substances, thereby activating further neighbored platelets, which finally can lead to the formation of thrombi. Prostanoids regulate the function of blood platelets by both activating or inhibiting and so are involved in hemostasis. Each prostanoid has a unique activity profile and, thus, a specific profile of action. This article reviews the effects of the following prostanoids: prostaglandin-D2 (PGD2), prostaglandin-E1, -E2 and E3 (PGE1, PGE2, PGE3), prostaglandin F2α (PGF2α), prostacyclin (PGI2) and thromboxane-A2 (TXA2) on platelet activation and aggregation via their respective receptors. Y1 - 2020 UR - https://www.mdpi.com/1422-0067/21/23/9020 U6 - https://doi.org/10.3390/ijms21239020 VL - 21 IS - 23 ER - TY - GEN A1 - Vagiannis, Dimitrios A1 - Zhang, Yu A1 - Budagaga, Youssif A1 - Novotna, Eva A1 - Skarka, Adam A1 - Kammerer, Sarah A1 - Küpper, Jan-Heiner A1 - Hofman, Jakub T1 - Alisertib shows negligible potential for perpetrating pharmacokinetic drug-drug interactions on ABCB1, ABCG2 and cytochromes P450, but acts as dual-activity resistance modulator through the inhibition of ABCC1 transporter T2 - Toxicology and Applied Pharmacology Y1 - 2022 U6 - https://doi.org/10.1016/j.taap.2021.115823 SN - 0041-008X VL - Vol. 434 ER - TY - GEN A1 - Braune, Steffen A1 - Krüger-Genge, Anne A1 - Köhler, S. A1 - Küpper, Jan-Heiner A1 - Jung, Friedrich T1 - Effects of Arthrospira platensis-derived substances on blood cells T2 - Clinical Hemorheology and Microcirculation Y1 - 2022 U6 - https://doi.org/10.3233/CH-229103 SN - 1875-8622 VL - 85(2023) IS - 3 SP - 315 EP - 321 ER - TY - GEN A1 - Jung, C. G. H. A1 - Nghinaunye, Theopolina A1 - Waldeck, Peter A1 - Braune, Steffen A1 - Petrick, Ingolf A1 - Küpper, Jan-Heiner A1 - Jung, Friedrich T1 - Decarbonization of Arthrospira platensis production by using atmospheric CO2 as an exclusive carbon source: proof of principle T2 - International Journal of Environmental Science and Technology N2 - There is an urgent need to develop technologies for removing CO2 from the atmosphere to combat climate change. Microalgae and cyanobacteria, such as Arthrospira platensis (AP), have shown promise due to their high photoautotrophic biomass production. Conventional AP culture media are supplemented with high concentrations of NaHCO3 since AP utilizes as a carbon source. These culture conditions result in significant amounts of CO2 escaping into the atmosphere, instead of being sequestered during cultivation. Here, we investigated whether ambient air (0.042% CO2) can be used for growing AP in a culture medium lacking a fossil-based carbon source. AP was cultured in 2 L glass bioreactors containing: (1) Zarrouk medium with 16.8 g/L NaHCO3 and aeration with 0.236 vvm air with 2% CO2 (“NaHCO3/CO2-based”) to compensate carbon loss due to CO2 outgassing, and (2) Zarrouk medium without NaHCO3 and a gas flow with ambient air (0.926 vvm) as the only carbon source (“air-based”). The air-based production resulted in the biofixation of 3.78 gCO2/L during the linear growth phase. With NaHCO3/CO2-based production, a comparable amount of 3.42 gCO2/L was obtained while 659.12 g of CO2 was released into the atmosphere. Total protein, phycocyanin, chlorophyll-a, and carotenoids were present in similar or increased amounts in AP produced by the air-based method. We concluded that cultivation of AP with Zarrouk medium lacking NaHCO3 but using ambient air with atmospheric CO2 as the only carbon source is possible without reducing productivity. These results improve our understanding of how atmospheric CO2 can be reduced by culturing AP. KW - Arthrospira platensis KW - Atmospheric CO2 KW - Biomass production KW - Climate change KW - Carbon capturing KW - Decarbonization Y1 - 2023 UR - https://link.springer.com/article/10.1007/s13762-023-05215-x#citeas U6 - https://doi.org/10.1007/s13762-023-05215-x SN - 1735-2630 ER - TY - GEN A1 - Haas, Manuel A1 - Ackermann, Gabriel A1 - Küpper, Jan-Heiner A1 - Glatt, Hansruedi A1 - Schrenk, Dieter A1 - Fahrer, Jörg T1 - OCT1-dependent uptake of structurally diverse pyrrolizidine alkaloids in human liver cells is crucial for their genotoxic and cytotoxic effects T2 - Archives of Toxicology N2 - Pyrrolizidine alkaloids (PAs) are important plant hepatotoxins, which occur as contaminants in plant-based foods, feeds and phytomedicines. Numerous studies demonstrated that the genotoxicity and cytotoxicity of PAs depend on their chemical structure, allowing for potency ranking and grouping. Organic cation transporter-1 (OCT1) was previously shown to be involved in the cellular uptake of the cyclic PA diesters monocrotaline, retrorsine and senescionine. However, little is known about the structure-dependent transport of PAs. Therefore, we investigated the impact of OCT1 on the uptake and toxicity of three structurally diverse PAs (heliotrine, lasiocarpine and riddelliine) differing in their degree and type of esterification in metabolically competent human liver cell models and hamster fibroblasts. Human HepG2-CYP3A4 liver cells were exposed to the respective PA in the presence or absence of the OCT1-inhibitors D-THP and quinidine, revealing a strongly attenuated cytotoxicity upon OCT1 inhibition. The same experiments were repeated in V79-CYP3A4 hamster fibroblasts, confirming that OCT1 inhibition prevents the cytotoxic effects of all tested PAs. Interestingly, OCT1 protein levels were much lower in V79-CYP3A4 than in HepG2-CYP3A4 cells, which correlated with their lower susceptibility to PA-induced cytotoxicity. The cytoprotective effect of OCT1 inhibiton was also demonstrated in primary human hepatocytes following PA exposure. Our experiments further showed that the genotoxic effects triggered by the three PAs are blocked by OCT1 inhibition as evidenced by strongly reduced γH2AX and p53 levels. Consistently, inhibition of OCT1-mediated uptake suppressed the activation of the DNA damage response (DDR) as revealed by decreased phosphorylation of checkpoint kinases upon PA treatment. In conclusion, we demonstrated that PAs, independent of their degree of esterification, are substrates for OCT1-mediated uptake into human liver cells. We further provided evidence that OCT1 inhibition prevents PA-triggered genotoxicity, DDR activation and subsequent cytotoxicity. These findings highlight the crucial role of OCT1 together with CYP3A4-dependent metabolic activation for PA toxicity. KW - Pyrrolizidine alkaloids KW - Cytotoxicity KW - Genotoxicity KW - OCT1 KW - Transport KW - Primary human hepatocytes KW - γH2AX KW - p53 Y1 - 2023 UR - https://link.springer.com/article/10.1007/s00204-023-03591-4 U6 - https://doi.org/10.1007/s00204-023-03591-4 SN - 1432-0738 SN - 0340-5761 VL - 97 IS - 12 SP - 3259 EP - 3271 ER - TY - GEN A1 - Jung, Conrad H. G. A1 - Waldeck, Peter A1 - Petrick, Ingolf A1 - Akinwunmi, Mosunmol A1 - Braune, Steffen A1 - Jung, Friedrich A1 - Küpper, Jan-Heiner T1 - Light-induced changes in the morphology and fluorescence of Arthrospira platensis T2 - Clinical Hemorheology and Microcirculation N2 - The cyanobacterium Arthrospira platensis is a well-known source of bioactive substances. Growth and the generation of bioactive ingredients of Arthrospira platensis depend mainly on the quantity of light in a controlled environment. Photoinhibition is a time, nutrient, and light intensity-dependent decrease in photosynthetic efficiency. However, too strong illumination can induce two harmful effects: (1) photoinhibition as a reduction in photosynthetic rate and (2) photooxidation which can have lethal effects on the cells, and which can lead to total loss of the culture. The results of this microscopical study demonstrate, that under the procedures described and very high photon flux den-sities, not only a decrease in the photosynthetic efficiency but beyond, also destruction of Arthrospira platensis can occur. KW - Arthrospira platensis KW - light stress KW - photoinhibition KW - phototoxicity KW - morphology KW - fluorescence Y1 - 2023 UR - https://content.iospress.com/articles/journal-of-cellular-biotechnology/jcb239001 U6 - https://doi.org/10.3233/JCB-239001 SN - 1386-0291 VL - 9 IS - 1 SP - 71 EP - 77 ER - TY - GEN A1 - Rosellini, Matteo A1 - Schulze, Alicia A1 - Omer, Ejlal A. A1 - Ali, Nadeen T. A1 - Marini, Federico A1 - Küpper, Jan-Heiner A1 - Efferth, Thomas T1 - The effect of plastic-related compounds on transcriptome-wide gene expression on CYP2C19-overexpressing HepG2 cells T2 - Molecules N2 - 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. KW - cytotoxicity KW - ecotoxicity KW - hepatotoxicity KW - microplastic KW - RNA sequencing Y1 - 2023 UR - https://www.mdpi.com/1420-3049/28/16/5952 U6 - https://doi.org/10.3390/molecules28165952 SN - 1420-3049 VL - 28 IS - 16 ER - TY - PAT A1 - Scheibner, Katrin A1 - Küpper, Jan-Heiner A1 - Schmidtke, Kai-Uwe A1 - Miethbauer, Sebastian A1 - Herzog, Natalie T1 - Verfahren zur Herstellung von biogenen Stoffen T1 - Method for producing biogenic substances Y1 - 2020 UR - https://patents.google.com/patent/EP3068868B1/de ER - TY - PAT A1 - Scheibner, Katrin A1 - Kiebist, Jan A1 - Schmidtke, Kai-Uwe A1 - Küpper, Jan-Heiner T1 - Verfahren zur enzymatischen Herstellung von zytostatischen 4-Hydroxy-Oxazaphosphorinen“ Y1 - 2020 UR - https://www.b-tu.de/enzymtechnologie/publikationen/patente ER - TY - PAT A1 - Scheibner, Katrin A1 - Küpper, Jan-Heiner A1 - Jung, Friedrich T1 - In vitro Arzneimittel aus Prodrugs und deren Verwendung Y1 - 2021 UR - https://www.b-tu.de/enzymtechnologie/publikationen/patente ER - TY - GEN A1 - Buchmueller, Julia A1 - Enge, Anne-Margarethe A1 - Peters, Antonia A1 - Ebmeyer, Johanna A1 - Küpper, Jan-Heiner A1 - Schäfer, Bernd A1 - Bräuning, Albert A1 - Hessel-Pras, Stefanie T1 - The chemical structure impairs the intensity of genotoxic effects promoted by 1,2-unsaturated pyrrolizidine alkaloids in vitro T2 - Food and Chemical Toxicology Y1 - 2022 U6 - https://doi.org/10.1016/j.fct.2022.113049 SN - 1873-6351 SN - 0278-6915 VL - Vol. 164 ER - TY - GEN A1 - Abdelfatah, Sara A1 - Nass, Janine A1 - Knorz, Caroline A1 - Klauck, Sabine M. A1 - Küpper, Jan-Heiner A1 - Efferth, Thomas T1 - Pyrrolizidine alkaloids cause cell cycle and DNA damage repair defects as analyzed by transcriptomics in cytochrome P450 3A4-overexpressing HepG2 clone 9 cells T2 - Cell biology and toxicology Y1 - 2022 U6 - https://doi.org/10.1007/s10565-021-09599-9 SN - 1573-6822 SN - 0742-2091 VL - 38 IS - 2 SP - 325 EP - 345 ER - TY - GEN A1 - Geburek, Ina A1 - Rutz, Lukas A1 - Gao, Lan A1 - Küpper, Jan-Heiner A1 - These, Anja A1 - Schrenk, Dieter T1 - The metabolic pattern of hepatotoxic pyrrolizidine alkaloids in liver cells T2 - Chemical Research in Toxicology N2 - 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. Y1 - 2021 UR - https://pubs.acs.org/doi/abs/10.1021/acs.chemrestox.0c00507 U6 - https://doi.org/10.1021/acs.chemrestox.0c00507 VL - 34 IS - 4 SP - 1101 EP - 1113 ER - TY - GEN A1 - Jung, Conrad H. G. A1 - Waldeck, Peter A1 - Petrick, Ingolf A1 - Braune, Steffen A1 - Küpper, Jan-Heiner A1 - Jung, Friedrich T1 - Bioreactor for the cultivation of Arthrospira platensis under controlled conditions T2 - Journal of Cellular Biotechnology N2 - 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. Y1 - 2021 UR - https://content.iospress.com/articles/journal-of-cellular-biotechnology/jcb210032 U6 - https://doi.org/10.3233/JCB-210032 VL - 7 IS - 1 SP - 35 EP - 40 ER - TY - GEN A1 - Braune, Steffen A1 - Krüger-Genge, Anne A1 - Kammerer, Sarah A1 - Jung, Friedrich A1 - Küpper, Jan-Heiner T1 - Phycocyanin from Arthrospira platensis as Potential Anti-Cancer Drug: Review of In Vitro and In Vivo Studies T2 - Life Y1 - 2021 UR - https://www.mdpi.com/2075-1729/11/2/91 U6 - https://doi.org/10.3390/life11020091 VL - 11 IS - 2 SP - 91 ER - TY - GEN A1 - Schulz, Christian A1 - Jung, Friedrich A1 - Küpper, Jan-Heiner T1 - Inhibition of phase-1 biotransformation and cytostatic effects of diphenyleneiodonium on hepatoblastoma cell line HepG2 and a CYP3A4-overexpressing HepG2 cell clone T2 - Clinical Hemorheology and Microcirculation N2 - 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. KW - Phase-1 KW - biotransformation KW - CYP KW - cytochrome P450 monooxygenase KW - CYP3A4 KW - diphenyleneiodonium KW - DPI KW - HepG2 KW - HepG2-CYP3A4 KW - hepatocytes KW - NADPH-cytochrome P450 oxidoreductase KW - POR KW - CPR Y1 - 2021 UR - https://content.iospress.com/articles/clinical-hemorheology-and-microcirculation/ch219117 U6 - https://doi.org/10.3233/CH-219117 SN - 1875-8622 SN - 1386-0291 VL - 79 IS - 1 SP - 231 EP - 243 ER - TY - GEN A1 - Krüger-Genge, Anne A1 - Jung, Conrad H. G. A1 - Braune, Steffen A1 - Harb, K. A1 - Westphal, S. A1 - Klöpzig, Stefanie A1 - Küpper, Jan-Heiner A1 - Jung, Friedrich T1 - Effect of Arthrospira powders from different producers on the formation of endothelial cell monolayers T2 - Clinical Hemorheology and Microcirculation N2 - Arthrospira platensis (AP) and some of its derived products have well-established biological activities as antioxidants or as agents to reduce cardiovascular disease risk factors. Furthermore, AP products have gained increasing importance as potential anti-cancer agents. However, the ingredients of the available products vary greatly with the origin, the type of production and processing, which could have significant consequences for their biological effects. Therefore, the composition and biological influence of five distinct AP powders, which were acquired commercially or produced at a public biotechnology institute, were investigated in regard to their endothelialization capacity using a cell impedance- (CI) based measurement method. The study revealed that the AP composition and especially the influence on HUVEC proliferation differed significantly between the five AP powders up to 109%. Thus, it could be shown that the method used allows the reliable detection of quantitative differences in biological effects of different AP preparations. KW - Arthrospira platensis KW - spirulina KW - endothelial cells Y1 - 2021 UR - https://content.iospress.com/articles/clinical-hemorheology-and-microcirculation/ch219200 U6 - https://doi.org/10.3233/CH-219200 SN - 1875-8622 SN - 1386-0291 VL - 79 IS - 1 SP - 193 EP - 203 ER - TY - GEN A1 - Krüger-Genge, Anne A1 - Steinbrecht, Susanne A1 - Küpper, Jan-Heiner A1 - Lendlein, Andreas A1 - Jung, Friedrich T1 - Evidence for cytostatic effect of cyclophosphamide on human vein endothelial cells in cancer therapy: preliminary in vitro results. T2 - Clinical Hemorheology and Microcirculation Y1 - 2018 U6 - https://doi.org/10.3233/CH-189125 SN - 1875-8622 SN - 1386-0291 VL - 69 IS - 1-2 SP - 267 EP - 276 ER - TY - GEN A1 - Jung, Friedrich A1 - Jung, Conrad H. G. A1 - Krüger-Genge, Anne A1 - Waldeck, Peter A1 - Küpper, Jan-Heiner T1 - Factors influencing the growth of Spirulina platensis in closed photobioreactors under CO₂ – O₂ conversion T2 - Journal of Cellular Biotechnology N2 - Since there is growing interest throughout the world in photosynthetic microbes as a potential source of food or food supplements, an assessment of factors which influence the biomass obtained in bioreactors, protein contents and constituents is important. This work reviews the autotrophic cultivation conditions of Spirulina platensis especially the dependency on the strain, the composition of the nutrient solution, pH, temperature of the medium, light intensity and color as well as exposure rhythm, the flow rate and composition of the aerating gas mixture and the bubble size, the content of oxygen, CO₂ and HCO₃ in the medium and last but not least from the optical density of the spirulina suspension during growth. KW - spirulina platensis KW - influencing factors KW - temperature KW - light intensity KW - wave length Y1 - 2019 U6 - https://doi.org/10.3233/JCB-199004 SN - 2352-3697 SN - 2352-3689 VL - 5 IS - 2 SP - 125 EP - 134 ER - TY - GEN A1 - Steinbrecht, Susanne A1 - König, Rosalie A1 - Schmidtke, Kai-Uwe A1 - Herzog, Natalie A1 - Scheibner, Katrin A1 - Krüger-Genge, Anne A1 - Jung, Friedrich A1 - Kammerer, Sarah A1 - Küpper, Jan-Heiner T1 - Metabolic activity testing can underestimate acute drug cytotoxicity as revealed by HepG2 cell clones overexpressing cytochrome P450 2C19 and 3A4 T2 - Toxicology Y1 - 2018 U6 - https://doi.org/10.1016/j.tox.2018.11.008 SN - 0300-483X VL - 412 SP - 37 EP - 47 ER - TY - GEN A1 - Kammerer, Sarah A1 - Küpper, Jan-Heiner T1 - Optimized protocol for induction of cytochrome P450 enzymes 1A2 and 3A4 in human primary-like hepatocyte cell strain HepaFH3 to study in vitro toxicology T2 - Clinical Hemorheology and Microcirculation Y1 - 2018 U6 - https://doi.org/10.3233/CH-189321 SN - 1386-0291 SN - 1875-8622 VL - 70 IS - 4 SP - 563 EP - 571 ER - TY - GEN A1 - Krüger-Genge, Anne A1 - Jung, Friedrich A1 - Küpper, Jan-Heiner A1 - Lehmann, Christian A1 - Franke, Ralf-Peter T1 - Actin type and distribution in erythrocytes T2 - Journal of Cellular Biotechnology N2 - Erythrocytes transport oxygen from the lungs to the tissues. The excess surface area together with the elasticity of the erythrocyte cell membrane provides the flexibility needed to pass through the microvasculature where the oxygen exchange occurs. Although the architecture of the red cell and its membrane-associated cytoskeletal network is known in general, the factors that control the characteristic shape change during echinocyte formation are poorly understood. In this short report we show that in echinocytes a completely reorganized membrane cytoskeleton with a box-like structure of actin filaments prevailed indicating the importance of the actin cytoskeleton during echinocyte formation. KW - Erythrocytes KW - echinocytes KW - submembraneous cytoskeleton KW - actin Y1 - 2018 UR - https://content.iospress.com/articles/journal-of-cellular-biotechnology/jcb179014 U6 - https://doi.org/10.3233/JCB-179014 SN - 2352-3697 SN - 2352-3689 VL - 3 IS - 2 SP - 81 EP - 83 ER - TY - GEN A1 - Krüger-Genge, Anne A1 - Braune, Steffen A1 - Walter, Maria A1 - Kratz, Karl A1 - Küpper, Jan-Heiner A1 - Krengel, M. A1 - Lendlein, Andreas A1 - Jung, Friedrich T1 - Influence of surface treatments of poly(n-butyl acrylate) networks on fibroblasts adhesion, morphology and viability T2 - Clinical Hemorheology and Microcirculation Y1 - 2018 U6 - https://doi.org/10.3233/CH-189130 SN - 1875-8622 SN - 1386-0291 VL - 69 IS - 1-2 SP - 305 EP - 316 ER - TY - GEN A1 - Nowak, Elisabeth A1 - Kammerer, Sarah A1 - Küpper, Jan-Heiner T1 - ATP-based cell viability assay is superior to trypan blue exclusion and XTT assay in measuring cytotoxicity of anticancer drugs Taxol and Imatinib, and proteasome inhibitor MG-132 on human hepatoma cell line HepG2. T2 - Clinical Hemorheology and Microcirculation Y1 - 2018 U6 - https://doi.org/10.3233/CH-189120 SN - 1386-0291 SN - 1875-8622 VL - 69 IS - 1-2 SP - 327 EP - 336 ER - TY - GEN A1 - Uhlig, Katja A1 - Gehre, Christian P. A1 - Kammerer, Sarah A1 - Küpper, Jan-Heiner A1 - Coleman, D. A1 - Püschel, G. A1 - Duschl, Claus T1 - Real-time monitoring of oxygen consumption of hepatocytes in a microbioreactor T2 - Toxicology Letters Y1 - 2018 U6 - https://doi.org/10.1016/j.toxlet.2018.06.652 SN - 0378-4274 VL - 295 IS - Supplement 1 SP - S115 ER - TY - PAT A1 - Küpper, Jan-Heiner T1 - Vorrichtung und Verfahren zur Sequestrierung von atmosphärischen Kohlendioxid Y1 - 2017 N1 - EU-Patentanmeldung ER - TY - GEN A1 - Nghinaunye, Theopolina A1 - Waldeck, Peter A1 - Jung, C. G. H. A1 - Küpper, Jan-Heiner A1 - Jung, Friedrich A1 - Braune, Steffen T1 - Response of Arthrospira platensis to different temperatures regarding growth and biochemical composition T2 - Clinical Hemorheology and Microcirculation N2 - The growth of cyanobacteria can vary considerably depending on the ambient temperature. Since the optimal growth temperature for Arthrospira platensis (strain SAG21.99) is not yet known, this was investigated in the present study. The study revealed that a process temperature of 30°C seems to be optimal for the Arthrospira strain SAG21.99 cultivation in terms of a maximum biomass productivity. This was also true for the phycocyanin content which was at 30°C significantly higher than at 20 or 40°C. KW - Arthrospira platensis KW - growth KW - temperature KW - bioreactor Y1 - 2023 UR - https://content.iospress.com/articles/clinical-hemorheology-and-microcirculation/ch238104 U6 - https://doi.org/10.3233/CH-238104 SN - 1386-0291 SP - 1 EP - 7 ER - TY - GEN A1 - Krüger-Genge, Anne A1 - Köhler, Susanne A1 - Laube, Markus A1 - Haileka, Vanessa A1 - Lemm, Sandy A1 - Majchrzak, Karolina A1 - Kammerer, Sarah A1 - Schulz, Christian A1 - Storsberg, Joachim A1 - Pietzsch, Jens A1 - Küpper, Jan-Heiner A1 - Jung, Friedrich T1 - Anti-Cancer Prodrug Cyclophosphamide Exerts Thrombogenic Effects on Human Venous Endothelial Cells Independent of CYP450 Activation—Relevance to Thrombosis T2 - Cells N2 - Cancer patients are at a very high risk of serious thrombotic events, often fatal. The causes discussed include the detachment of thrombogenic particles from tumor cells or the adverse effects of chemotherapeutic agents. Cytostatic agents can either act directly on their targets or, in the case of a prodrug approach, require metabolization for their action. Cyclophosphamide (CPA) is a widely used cytostatic drug that requires prodrug activation by cytochrome P450 enzymes (CYP) in the liver. We hypothesize that CPA could induce thrombosis in one of the following ways: (1) damage to endothelial cells (EC) after intra-endothelial metabolization; or (2) direct damage to EC without prior metabolization. In order to investigate this hypothesis, endothelial cells (HUVEC) were treated with CPA in clinically relevant concentrations for up to 8 days. HUVECs were chosen as a model representing the first place of action after intravenous CPA administration. No expression of CYP2B6, CYP3A4, CYP2C9 and CYP2C19 was found in HUVEC, but a weak expression of CYP2C18 was observed. CPA treatment of HUVEC induced DNA damage and a reduced formation of an EC monolayer and caused an increased release of prostacyclin (PGI2) and thromboxane (TXA) associated with a shift of the PGI2/TXA balance to a prothrombotic state. In an in vivo scenario, such processes would promote the risk of thrombus formation. KW - cancer KW - cyclophosphamide KW - human umbilical vein endothelial cells KW - HUVEC KW - liver KW - cytochrome P450 enzymes (CYP) KW - thrombosis Y1 - 2023 UR - https://www.mdpi.com/2073-4409/12/15/1965 U6 - https://doi.org/10.3390/cells12151965 SN - 2073-4409 VL - 12 IS - 15 ER - TY - GEN A1 - Haas, Manuel A1 - Wirachowski, Karina A1 - Thibol, Lea A1 - Küpper, Jan-Heiner A1 - Schrenk, Dieter A1 - Fahrer, Jörg T1 - Potency ranking of pyrrolizidine alkaloids in metabolically competent human liver cancer cells and primary human hepatocytes using a genotoxicity test battery T2 - Archives of Toxicology N2 - Pyrrolizidine alkaloids (PAs) occur as contaminants in plant-based foods and herbal medicines. Following metabolic activation by cytochrome P450 (CYP) enzymes, PAs induce DNA damage, hepatotoxicity and can cause liver cancer in rodents. There is ample evidence that the chemical structure of PAs determines their toxicity. However, more quantitative genotoxicity data are required, particularly in primary human hepatocytes (PHH). Here, the genotoxicity of eleven structurally different PAs was investigated in human HepG2 liver cells with CYP3A4 overexpression and PHH using an in vitro test battery. Furthermore, the data were subject to benchmark dose (BMD) modeling to derive the genotoxic potency of individual PAs. The cytotoxicity was initially determined in HepG2-CYP3A4 cells, revealing a clear structure–toxicity relationship for the PAs. Importantly, experiments in PHH confirmed the structure-dependent toxicity and cytotoxic potency ranking of the tested PAs. The genotoxicity markers γH2AX and p53 as well as the alkaline Comet assay consistently demonstrated a structure-dependent genotoxicity of PAs in HepG2-CYP3A4 cells, correlating well with their cytotoxic potency. BMD modeling yielded BMD values in the range of 0.1–10 µM for most cyclic and open diesters, followed by the monoesters. While retrorsine showed the highest genotoxic potency, monocrotaline and lycopsamine displayed the lowest genotoxicity. Finally, experiments in PHH corroborated the genotoxic potency ranking, and revealed genotoxic effects even in the absence of detectable cytotoxicity. In conclusion, our findings strongly support the concept of grouping PAs into potency classes and help to pave the way for a broader acceptance of relative potency factors in risk assessment. KW - Cytotoxicity KW - Genotoxicity KW - Benchmark dose modeling KW - Pyrrolizidine alkaloids KW - Primary human hepatocytes KW - Potency ranking KW - γH2AX KW - p53 KW - DNA damage Y1 - 2023 UR - https://link.springer.com/article/10.1007/s00204-023-03482-8 U6 - https://doi.org/10.1007/s00204-023-03482-8 SN - 0340-5761 VL - 97 IS - 5 SP - 1413 EP - 1428 ER - TY - GEN A1 - Krüger-Genge, Anne A1 - Jung, Friedrich A1 - Hufert, Frank A1 - Jung, Ernst Michael A1 - Küpper, Jan-Heiner A1 - Storsberg, J. T1 - Effects of gut microbial metabolite trimethylamine N-oxide (TMAO) on platelets and endothelial cells T2 - Clinical Hemorheology and Microcirculation N2 - Thrombotic events result from different pathologies and are the underlying causes of severe diseases like stroke or myocardial infarction. Recent basic research now revealed a link between food uptake, food conversion and gut metabolism. Gut microbial production of trimethylamine N-oxide (TMAO) from dietary nutrients like choline, lecithin and L-carnitine was associated with the development of cardiovascular diseases. Within this review we give a systematic overview about the influence of TMAO on blood components like platelets and endothelial cells which both are involved as key players in thrombotic processes. In summary, a mechanistic correlation between the gut microbiome, TMAO and cardiovascular diseases becomes obvious and emphasizes to the significance of the intestinal microbiome. KW - Microbiome KW - trimethylamin-N-oxide KW - platelets KW - endothelial cells KW - atherosclerosis Y1 - 2020 UR - https://content.iospress.com/articles/clinical-hemorheology-and-microcirculation/ch209206 U6 - https://doi.org/10.3233/CH-209206 SN - 1875-8622 SN - 1386-0291 VL - 76 IS - 2 SP - 309 EP - 316 ER - TY - GEN A1 - Rahman, Ateeq A1 - Moola, Nyambe A1 - Küpper, Jan-Heiner T1 - Namibian algae species: A review of their distribution, medicinal uses and chemical constituents T2 - Journal of Cellular Biotechnology N2 - The use of indigenous or remote popular knowledge to identify new drugs against diseases or infections is a well-known approach in medicine. The inhabitants of coastal regions in Namibia and other African countries are known to prepare algae extracts for the treatment of disorders and ailments such as wounds, fever and stomach aches, as well as for the prevention of arrhythmia, cancer, and many other diseases. Algae survive in a competitive environment and, therefore, developed defense strategies that have resulted in a significant level of chemical structural diversity in various metabolic pathways. The exploration of these organisms for pharmaceutical, nutritional and medical purposes has provided important chemical candidates for the discovery of new agents against neglected tropical diseases and stimulated the use of sophisticated physical techniques. This current review provides a broad picture on the taxonomy, various medical and nutritional uses of algae, which thus should be of relevance for the African continent and underdeveloped countries in the Global South. Y1 - 2020 UR - https://content.iospress.com/articles/journal-of-cellular-biotechnology/jcb209010 U6 - https://doi.org/10.3233/JCB-209010 VL - 6 IS - 2 SP - 139 EP - 159 ER - TY - GEN A1 - Gehre, Christian P. A1 - Flechner, Marie A1 - Kammerer, Sarah A1 - Küpper, Jan-Heiner A1 - Coleman, Charles Dominic A1 - Püschel, Gerhard Paul A1 - Uhlig, Katja A1 - Duschl, Claus T1 - Real time monitoring of oxygen uptake of hepatocytes in a microreactor using optical microsensors T2 - Scientific Reports N2 - Most in vitro test systems for the assessment of toxicity are based on endpoint measurements and cannot contribute much to the establishment of mechanistic models, which are crucially important for further progress in this field. Hence, in recent years, much effort has been put into the development of methods that generate kinetic data. Real time measurements of the metabolic activity of cells based on the use of oxygen sensitive microsensor beads have been shown to provide access to the mode of action of compounds in hepatocytes. However, for fully exploiting this approach a detailed knowledge of the microenvironment of the cells is required. In this work, we investigate the cellular behaviour of three types of hepatocytes, HepG2 cells, HepG2-3A4 cells and primary mouse hepatocytes, towards their exposure to acetaminophen when the availability of oxygen for the cell is systematically varied. We show that the relative emergence of two modes of action, one NAPQI dependent and the other one transient and NAPQI independent, scale with expression level of CYP3A4. The transient cellular response associated to mitochondrial respiration is used to characterise the influence of the initial oxygen concentration in the wells before exposure to acetaminophen on the cell behaviour. A simple model is presented to describe the behaviour of the cells in this scenario. It demonstrates the level of control over the role of oxygen supply in these experiments. This is crucial for establishing this approach into a reliable and powerful method for the assessment of toxicity. KW - Biophysics KW - Biotechnology KW - Cell biology KW - Drug discovery Y1 - 2020 UR - https://www.nature.com/articles/s41598-020-70785-6 U6 - https://doi.org/10.1038/s41598-020-70785-6 SN - 2045-2322 VL - 10 ER - TY - GEN A1 - Steinbrecht, Susanne A1 - Kammerer, Sarah A1 - Küpper, Jan-Heiner T1 - HepG2 cells with recombinant cytochrome P450 enzyme overexpression: Their use and limitation as in vitro liver model T2 - Journal of Cellular Biotechnology Y1 - 2019 U6 - https://doi.org/10.3233/JCB-189013 SN - 2352-3697 SN - 2352-3689 VL - 5 IS - 1 SP - 55 EP - 64 ER - TY - GEN A1 - Schulz, Christian A1 - Kammerer, Sarah A1 - Küpper, Jan-Heiner T1 - NADPH-cytochrome P450 reductase expression and enzymatic activity in primary-like human hepatocytes and HepG2 cells for in vitro biotransformation studies T2 - Clinical Hemorheology and Microcirculation Y1 - 2019 U6 - https://doi.org/10.3233/CH-199226 SN - 1386-0291 VL - 73 IS - 1 SP - 249 EP - 260 ER - TY - GEN A1 - Hofman, Jakub A1 - Sorf, Ales A1 - Vagiannis, Dimitrios A1 - Sucha, Simona A1 - Kammerer, Sarah A1 - Küpper, Jan-Heiner A1 - Chen, Si A1 - Guo, Lei A1 - Ceckova, Martina A1 - Staud, Frantisek T1 - Brivanib Exhibits Potential for Pharmacokinetic Drug-Drug Interactions and the Modulation of Multidrug Resistance through the Inhibition of Human ABCG2 Drug Efflux Transporter and CYP450 Biotransformation Enzymes T2 - Molecular Pharmaceutics Y1 - 2019 U6 - https://doi.org/10.1021/acs.molpharmaceut.9b00361 VL - 16 IS - 11 SP - 4436 EP - 4450 ER - TY - GEN A1 - Hofman, Jakub A1 - Sorf, Ales A1 - Vagiannis, Dimitrios A1 - Sucha, Simona A1 - Novotna, Eva A1 - Kammerer, Sarah A1 - Küpper, Jan-Heiner A1 - Ceckova, Martina A1 - Staud, Frantisek T1 - Interactions of Alectinib with Human ATP-Binding Cassette Drug Efflux Transporters and Cytochrome P450 Biotransformation Enzymes: Effect on Pharmacokinetic Multidrug Resistance T2 - Drug Metabolism and Disposition Y1 - 2019 U6 - https://doi.org/10.1124/dmd.119.086975 SN - 1521-009X SN - 0090-9556 VL - 47 IS - 7 SP - 699 EP - 709 ER - TY - GEN A1 - Jung, Friedrich A1 - Krüger-Genge, Anne A1 - Waldeck, Peter A1 - Küpper, Jan-Heiner T1 - Spirulina platensis, a super food? T2 - Journal of Cellular Biotechnology N2 - Spirulina platensis, a multicelluar, photosynthetic prokaryote (algae) contains a high amount of proteins, vitamins and minerals superior to many foods as e.g. soybeans. Thus, Spirulina platensis was recognized as nutritious food by the United Nations World Food Conference. Due to the high amount of nutritive ingredients Spirulina has a long history as dietary supplement. In addition, spirulina platensis is also efficiently used as forage with known effects on flesh, egg and plumage color, milk yield and fertility. The versatile utilization of the alga can be explained on the one hand with the nutrient levels and on the other hand with recognized effects as anti-viral, anti-bacterial, anti-oxidant, anti-diabetic, anti-cancer and anti-inflammatory substance. Therefore, this alga is named as “superfood”. Beyond, these algae convert carbon dioxide into organic substances and produce oxygen during their growth in alkaline and saline water thereby not wasting fresh water allowing the production in barren areas. Despite this diverse use of Spirulina platensis due to its beneficial properties, many basic mechanisms on a molecular and cellular level are not well understood and should be explored in future studies. KW - Spirulina KW - health effects KW - dietary supplements KW - liver protection KW - virus infection KW - HIV KW - nutrition KW - animal feeding Y1 - 2019 UR - https://content.iospress.com/articles/journal-of-cellular-biotechnology/jcb189012 U6 - https://doi.org/10.3233/JCB-189012 SN - 2352-3689 SN - 2352-3697 VL - 5 IS - 1 SP - 43 EP - 54 ER - TY - GEN A1 - Jung, Conrad H. G. A1 - Waldeck, Peter A1 - Sykora, Shadi A1 - Braune, Steffen A1 - Petrick, Ingolf A1 - Küpper, Jan-Heiner A1 - Jung, Friedrich T1 - Influence of Different Light-Emitting Diode Colors on Growth and Phycobiliprotein Generation of Arthrospira platensis T2 - Life Y1 - 2022 U6 - https://doi.org/10.3390/life12060895 SN - 2075-1729 VL - 12 IS - 6 ER - TY - GEN A1 - Lemm, Sandy A1 - Köhler, Susanne A1 - Wodtke, Robert A1 - Jung, Friedrich A1 - Küpper, Jan-Heiner A1 - Pietzsch, Jens A1 - Laube, Markus T1 - Investigation of radiotracer metabolic stability in vitro with CYP-overexpressing hepatoma cell lines T2 - Cells Y1 - 2022 U6 - https://doi.org/10.3390/cells11152447 SN - 2073-4409 VL - 11 IS - 15 ER - TY - GEN A1 - Lemm, Sandy A1 - Köhler, Susanne A1 - Wodtke, Robert A1 - Jung, Friedrich A1 - Küpper, Jan-Heiner A1 - Pietzsch, Jens A1 - Laube, Markus T1 - Enabling insights into the cytochrome P450 isoform specific metabolism of radiotracers by CYP overexpressing hepatoblastoma cell lines T2 - Nuclear Medicine and Biology Y1 - 2022 SN - 1872-9614 IS - 108-109, Supplement  SP - S66 EP - S67 ER - TY - GEN A1 - Jung, Friedrich A1 - Braune, Steffen A1 - Jung, Conrad H. G. A1 - Krüger-Genge, Anne A1 - Waldeck, Peter A1 - Petrick, Ingolf A1 - Küpper, Jan-Heiner T1 - Lipophilic and Hydrophilic Compounds from Arthrospira platensis and Its Effects on Tissue and Blood Cells—An Overview T2 - Life Y1 - 2022 U6 - https://doi.org/10.3390/life12101497 SN - 2075-1729 VL - 12 IS - 10 ER - TY - GEN A1 - Jung, Conrad H. G. A1 - Braune, Steffen A1 - Waldeck, Peter A1 - Küpper, Jan-Heiner A1 - Petrick, Ingolf A1 - Jung, Friedrich T1 - Morphology and Growth of Arthrospira platensis during Cultivation in a Flat-Type Bioreactor T2 - Life N2 - Arthrospira platensis (AP) is a cyanobacterium with a high economic value and is nowadays one of the most important industrially cultivated microalgae. Knowledge of its growth is essential for the understanding of its physiology and yield. The growth of AP biomass occurs through two mechanisms: (1) propagation by fragmentation of trichomes, and (2) the trichomes are extended by binary fission until they reach their mature status. These phases are visualized by live cell light and laser scanning microscopy, demonstrating the different phases of AP growth. KW - Arthrospira platensis KW - Spirulina KW - life cycle KW - morphology KW - fragmentation KW - fission Y1 - 2021 UR - https://www.mdpi.com/2075-1729/11/6/536/htm U6 - https://doi.org/10.3390/life11060536 SN - 2075-1729 VL - 11 IS - 6 ER - TY - GEN A1 - Küpper, Jan-Heiner A1 - Krüger-Genge, Anne A1 - Jung, Friedrich T1 - 40th conference of the German society for clinical microcirculation and hemorheology (DGKMH) T2 - Clinical Hemorheology and Microcirculation Y1 - 2021 U6 - https://doi.org/10.3233/ch-219100 SN - 1875-8622 SN - 1386-0291 VL - 79 IS - 1 SP - 1 EP - 2 ER - TY - GEN A1 - Steinbrecht, Susanne A1 - Pfeifer, Nadine A1 - Herzog, Natalie A1 - Katzenberger, Nadine A1 - Schulz, Christian A1 - Kammerer, Sarah A1 - Küpper, Jan-Heiner T1 - HepG2-1A2 C2 and C7: Lentivirus vector-mediated stable and functional overexpression of cytochrome P450 1A2 in human hepatoblastoma cells T2 - Toxicology Letters N2 - Novel HepG2 cell clones 1A2 C2 and 1A2 C7 were independently generated by lentiviral transduction to functionally overexpress cytochrome P450 1A2 (CYP1A2). We found similar and stable CYP1A2 transcript and protein levels in both cell clones leading to specific enzyme activities of about 370 pmol paracetamol x min-1 x mg-1 protein analyzed by phenacetin conversion. Both clones showed dramatically increased sensitivity to the hepatotoxic compound aflatoxin B1 (EC50<100 nM) when compared to parental HepG2 cells (EC50 ∼5 μM). Thus, newly established cell lines are an appropriate tool to study metabolism and toxicity of substances depending on conversion by CYP1A2. KW - HepG2 KW - CYP1A2 KW - Cytochrome P450 KW - Liver metabolism Y1 - 2020 U6 - https://doi.org/10.1016/j.toxlet.2019.11.006 SN - 0378-4274 VL - 319 SP - 155 EP - 159 ER - TY - GEN A1 - Haas, M. A1 - Wirachowski, K. A1 - Küpper, Jan-Heiner A1 - Schrenk, Dieter A1 - Fahrer, J. T1 - Structure‐dependent genotoxicity and cytotoxicity of eleven pyrrolizidine alkaloids in human liver cells with CYP3A4 overexpression T2 - Lebensmittelchemie : Volume 75: Vorträge und Poster des 49. Deutschen Lebensmittelchemikertags Y1 - 2021 U6 - https://doi.org/10.1002/lemi.202158135 SN - 0937-1478 SN - 1521-3811 SP - S134 ER - TY - PAT A1 - Küpper, Jan-Heiner A1 - Jung, Friedrich T1 - Arthrospira for use in the treatment of diseases Y1 - 2021 UR - https://www.google.de/url?sa=t&rct=j&q=&esrc=s&source=web&cd=&cad=rja&uact=8&ved=2ahUKEwik1t7QrOL5AhVTO-wKHT97CKAQFnoECAQQAQ&url=https%3A%2F%2Fdata.epo.org%2Fpublication-server%2Frest%2Fv1.0%2Fpublication-dates%2F20220302%2Fpatents%2FEP3960193NWA1%2Fdocument.pdf&usg=AOvVaw20GVY_ywjb2xbS0TwSDArJ ER - TY - GEN A1 - Vagiannis, Dimitrios A1 - Budagaga, Youssif A1 - Morell, Anselm A1 - Zhang, Yu A1 - Novotna, Eva A1 - Skarka, Adam A1 - Kammerer, Sarah A1 - Küpper, Jan-Heiner A1 - Hanke, Ivo A1 - Rozkoš, Tomáš A1 - Hofman, Jakub T1 - Tepotinib Inhibits Several Drug Efflux Transporters and Biotransformation Enzymes: The Role in Drug-Drug Interactions and Targeting Cytostatic Resistance In Vitro and Ex Vivo T2 - International Journal of Molecular Sciences Y1 - 2021 U6 - https://doi.org/10.3390/ijms222111936 SN - 1422-0067 SN - 1661-6596 VL - 22 IS - 21 ER - TY - GEN A1 - Künzel, Stephan R. A1 - Hoffmann, Maximilian A1 - Weber, Silvio A1 - Künzel, Karolina A1 - Kämmerer, Susanne A1 - Günscht, Mario A1 - Klapproth, Erik A1 - Rausch, Johanna S. E. A1 - Sadek, Mirna S. A1 - Kolanowski, Tomasz A1 - Meyer-Roxlau, Stefanie A1 - Piorkowski, Christopher A1 - Tugtekin, Sems M. A1 - Rose-John, Stefan A1 - Yin, Xiaoke A1 - Mayr, Manuel A1 - Kuhlmann, Jan Dominik A1 - Wimberger, Pauline A1 - Grützmann, Konrad A1 - Herzog, Natalie A1 - Küpper, Jan-Heiner A1 - O’Reilly, Molly A1 - Kabir, S. Nashitha A1 - Sommerfeld, Laura C. A1 - Guan, Kaomei A1 - Wielockx, Ben A1 - Fabritz, Larissa A1 - Nattel, Stanley A1 - Ravens, Ursula A1 - Dobrev, Dobromir A1 - Wagner, Michael A1 - El-Armouche, Ali T1 - Diminished PLK2 Induces Cardiac Fibrosis and Promotes Atrial Fibrillation T2 - Circulation Research N2 - Rationale: Fibrosis promotes the maintenance of atrial fibrillation (AF), making it resistant to therapy. Improved understanding of the molecular mechanisms leading to atrial fibrosis will open new pathways toward effective antifibrotic therapies. Objective: This study aims to decipher the mechanistic interplay between PLK2 (polo-like kinase 2) and the profibrotic cytokine OPN (osteopontin) in the pathogenesis of atrial fibrosis and AF. Methods and Results: Atrial PLK2 mRNA expression was 10-fold higher in human fibroblasts than in cardiomyocytes. Compared with sinus rhythm, right atrial appendages and isolated right atrial fibroblasts from patients with AF showed downregulation of PLK2 mRNA and protein, along with increased PLK2 promotor methylation. Genetic deletion as well as pharmacological inhibition of PLK2 induced profibrotic phenotype conversion in cardiac fibroblasts and led to a striking de novo secretion of OPN. Accordingly, PLK2-deficient (PLK2 knockout) mice showed cardiac fibrosis and were prone to experimentally induced AF. In line with these findings, OPN plasma levels were significantly higher only in patients with AF with atrial low-voltage zones (surrogates of fibrosis) compared with sinus rhythm controls. Mechanistically, we identified ERK1/2 as the relevant downstream mediator of PLK2 leading to increased OPN expression. Finally, oral treatment with the clinically available drug mesalazine, known to inhibit ERK1/2, prevented cardiac OPN overexpression and reversed the pathological PLK2 knockout phenotype in PLK2 knockout mice. Conclusions: Abnormal PLK2/ERK1/2/OPN axis function critically contributes to AF-related atrial fibrosis, suggesting reinforcing PLK2 activity and/or OPN inhibition as innovative targets to prevent fibrosis progression in AF. Mesalazine derivatives may be used as lead compounds for the development of novel anti-AF agents targeting fibrosis. KW - atrial fibrillation KW - fibroblasts KW - fibrosis KW - mesalamine KW - osteopontin Y1 - 2021 UR - https://www.ahajournals.org/doi/full/10.1161/CIRCRESAHA.121.319425 U6 - https://doi.org/10.1161/CIRCRESAHA.121.319425 SN - 1524-4571 SN - 0009-7330 VL - 129 IS - 8 SP - 804 EP - 820 ER - TY - GEN A1 - Lau, S. A1 - Rangarajan, R. A1 - Krüger-Genge, Anne A1 - Braune, Steffen A1 - Kammerer, Sarah A1 - Küpper, Jan-Heiner A1 - Lendlein, Andreas A1 - Jung, Friedrich T1 - Effects of acrolein in comparison to its prodrug cyclophosphamide on human primary endothelial cells in vitro T2 - Toxicology in Vitro N2 - Cyclophosphamide (CPA) is one of the most successful anticancer prodrugs that becomes effective after biotransformation in the liver resulting in the toxic metabolite acrolein. Cancer is often accompanied by thromboembolic events, which might be a result of dysfunctional endothelial cells due to CPA treatment. Here, the effect of 1 mM CPA or acrolein (10/50/100/500 μM) on human umbilical vein endothelial cells (HUVECs) was analyzed after two days of treatment. The addition of CPA or 10 μM acrolein did not affect HUVECs. However, concentrations of 100 μM and 500 μM acrolein significantly reduced the number of adherent cells by 86 ± 13% and 99 ± 1% and cell viability by 51 ± 29% and 93 ± 8% compared to the control. Moreover, pronounced stress fibers as well as multiple nuclei were observed and von Willebrand factor (vWF) was completely released. Lactate dehydrogenase was 8.5 ± 7.0-fold and 252.9 ± 42.9-fold increased showing a loss of cell membrane integrity. The prostacyclin and thromboxane secretion was significantly increased by the addition of 500 μM acrolein (43.1 ± 17.6-fold and 246.4 ± 106.3-fold) indicating cell activation/pertubation. High doses of acrolein led to HUVEC death and loss of vWF production. This effect might be associated with the increased incidence of thromboembolic events in cancer patients treated with high doses of CPA. KW - Human umbilical venous endothelial cells KW - Acrolein KW - Aneuploidy KW - von Willebrand factor KW - in vitro study Y1 - 2020 U6 - https://doi.org/10.1016/j.tiv.2019.104685 SN - 0887-2333 VL - 62 ER - TY - GEN A1 - Küpper, Jan-Heiner A1 - Jung, Friedrich A1 - Krieger, Volker A1 - Hufert, Frank T1 - A comparison of mortality rates between European and Asian States T2 - Clinical Hemorheology and Microcirculation Y1 - 2020 U6 - https://doi.org/10.3233/CH-209008 SN - 1875-8622 SN - 1386-0291 VL - 75 IS - 1 SP - 3 EP - 5 ER - TY - GEN A1 - Vagiannis, Dimitrios A1 - Novotna, Eva A1 - Skarka, Adam A1 - Kammerer, Sarah A1 - Küpper, Jan-Heiner A1 - Chen, Si A1 - Guo, Lei A1 - Staud, Frantisek A1 - Hofman, Jakub T1 - Ensartinib (X-396) Effectively Modulates Pharmacokinetic Resistance Mediated by ABCB1 and ABCG2 Drug Efflux Transporters and CYP3A4 Biotransformation Enzyme T2 - Cancers N2 - Ensartinib (X-396) is a promising tyrosine kinase inhibitor currently undergoing advanced clinical evaluation for the treatment of non-small cell lung cancer. In this work, we investigate possible interactions of this promising drug candidate with ATP-binding cassette (ABC) drug efflux transporters and cytochrome P450 biotransformation enzymes (CYPs), which play major roles in multidrug resistance (MDR) and pharmacokinetic drug-drug interactions (DDIs). Accumulation studies showed that ensartinib is a potent inhibitor of ABCB1 and ABCG2 transporters. Additionally, incubation experiments with recombinant CYPs showed that ensartinib significantly inhibits CYP3A4 and CYP2C9. Subsequent molecular docking studies confirmed these findings. Drug combination experiments demonstrated that ensartinib synergistically potentiates the antiproliferative effects of daunorubicin, mitoxantrone, and docetaxel in ABCB1, ABCG2, and CYP3A4-overexpressing cellular models, respectively. Advantageously, ensartinib’s antitumor efficiency was not compromised by the presence of MDR-associated ABC transporters, although it acted as a substrate of ABCB1 in Madin-Darby Canine Kidney II (MDCKII) monolayer transport assays. Finally, we demonstrated that ensartinib had no significant effect on the mRNA-level expression of examined transporters and enzymes in physiological and lung tumor cellular models. In conclusion, ensartinib may perpetrate clinically relevant pharmacokinetic DDIs and modulate ABCB1-, ABCG2-, and CYP3A4-mediated MDR. The in vitro findings presented here will provide a valuable foundation for future in vivo investigations. KW - ensartinib KW - cancer KW - multidrug resistance KW - drug-drug interaction KW - ABC transporter KW - cytochrome P450 Y1 - 2020 UR - https://www.mdpi.com/2072-6694/12/4/813 U6 - https://doi.org/10.3390/cancers12040813 SN - 2072-6694 VL - 12 IS - 4 ER - TY - GEN A1 - Jung, Friedrich A1 - Krieger, Volker A1 - Hufert, Frank A1 - Küpper, Jan-Heiner T1 - How we should respond to the Coronavirus SARS-CoV-2 outbreak: A German perspective T2 - Clinical Hemorheology and Microcirculation N2 - BACKGROUND: In the early phase of the COVID-19 pandemic Germany missed to set up efficient containment measures. Consequently, the number of cases increased exponentially until a lockdown was implemented to suppress the spread of SARS-CoV-2. Fortunately, Germany has a high capability for coronavirus lab testing and more than 30,000 ICU beds. These capabilities and the lockdown turned out to be an advantage to combat the pandemic and to prevent a health-system overload. AIM: The aim was to predict the plateau day of SARS-CoV-2 infections or deaths. RESULTS: The effect on the viral spread of the German measures taken and the impact on the peak of new infection cases is shown. By normalizing daily case numbers, the plateau day of the current outbreak in Germany could be calculated to be reached at April 12, 2020 (day 103 of 2020). CONCLUSION: Normalized case number curves are helpful to predict the time point at which no further new infections will occur if the epidemic situation remains stable. Upon reaching the plateau day during a lockdown phase, a residual time-period of about 2-3 weeks can be utilized to prepare a safe unlocking period. As can be learned from Asian countries such as South Korea and Taiwan there must be strict rules to keep the risk of infection low. Those include social distancing, face mask wearing in combination with digital contact tracing and serosurveillance studies. Following those rules, a safe dance around the infection curve allows to keep the population at a reduced infection rate. KW - Corona virus KW - SARS-CoV-2 KW - COVID-19 KW - herd immunity KW - hammer and dance strategy Y1 - 2020 UR - https://content.iospress.com/articles/clinical-hemorheology-and-microcirculation/ch209004 U6 - https://doi.org/10.3233/CH-209004 SN - 1875-8622 SN - 1386-0291 VL - 74 IS - 4 SP - 363 EP - 372 ER - TY - GEN A1 - Kammerer, Sarah A1 - Nowak, Elisabeth A1 - Mantke, René A1 - Jung, Friedrich A1 - Küpper, Jan-Heiner T1 - In vitro simulation of the liver first-pass effect with biotransformation-competent HepG2 cells to study effects of MG-132 on liver and cancer cells T2 - Clinical Hemorheology and Microcirculation N2 - BACKGROUND: Liver biotransformation is the major route for drug metabolism in humans, often catalysed by cytochrome P450 (CYP) enzymes. This first-pass effect can lead to hepatotoxicity and influences the bioavailability of drugs. OBJECTIVE: We aimed to establish in vitro culture systems simulating the liver first-pass to study effects of the proteasome inhibitor MG-132 simultaneously on hepatocytes and cancer cells. METHODS: The first-pass effect was simulated by conditioned medium transfer (CMT) from pre-treated HepG2 CYP3A4-overexpressing cells to either pancreatic cancer cell line PANC-1 or primary colon cancer cells, and by indirect co-culture (CC) of liver and cancer cells in a shared medium compartment. Experimental proteasome inhibitor MG-132 was used as test substance as it is detoxified by CYP3A4. RESULTS: Cancer cells showed higher viabilities in the first-pass simulation by CMT and CC formats when compared to monocultures indicating effective detoxification of MG-132 by HepG2 CYP3A4-overexpressing cells. HepG2-CYP3A4 cells showed reduced viabilites after treatment with MG-132. CONCLUSIONS: We successfully established two different culture systems to simulate the liver first-pass effect in vitro. Such systems easily allow to study drug effects simultaneously on liver and on target cancer cells. They are of great value in pre-clinical cancer research, pharmaceutical research and drug development. KW - Liver biotransformation KW - first-pass effect KW - CYP3A4 KW - MG-132 KW - cancer cells KW - in vitro culture systems Y1 - 2024 UR - https://content.iospress.com/articles/clinical-hemorheology-and-microcirculation/ch238108 U6 - https://doi.org/10.3233/CH-238108 SN - 1386-0291 VL - 86 IS - 1-2 SP - 159 EP - 168 ER - TY - GEN A1 - Schulz, Christian A1 - Herzog, Natalie A1 - Kubick, Stefan A1 - Jung, Friedrich A1 - Küpper, Jan-Heiner T1 - Stable Chinese Hamster Ovary Suspension Cell Lines Harboring Recombinant Human Cytochrome P450 Oxidoreductase and Human Cytochrome P450 Monooxygenases as Platform for In Vitro Biotransformation Studies T2 - Cells N2 - In the liver, phase-1 biotransformation of drugs and other xenobiotics is largely facilitated by enzyme complexes consisting of cytochrome P450 oxidoreductase (CPR) and cytochrome P450 monooxygenases (CYPs). Generated from human liver-derived cell lines, recombinant in vitro cell systems with overexpression of defined phase-1 enzymes are widely used for pharmacological and toxicological drug assessment and laboratory-scale production of drug-specific reference metabolites. Most, if not all, of these cell lines, however, display some background activity of several CYPs, making it difficult to attribute effects to defined CYPs. The aim of this study was to generate cell lines with stable overexpression of human phase-1 enzymes based on Chinese hamster ovary (CHO) suspension cells. Cells were sequentially modified with cDNAs for human CPR in combination with CYP1A2, CYP2B6, or CYP3A4, using lentiviral gene transfer. In parallel, CYP-overexpressing cell lines without recombinant CPR were generated. Successful recombinant expression was demonstrated by mRNA and protein analyses. Using prototypical CYP-substrates, generated cell lines proved to display specific enzyme activities of each overexpressed CYP while we did not find any endogenous activity of those CYPs in parental CHO cells. Interestingly, cell lines revealed some evidence that the dependence of CYP activity on CPR could vary between CYPs. This needs to be confirmed in further studies. Recombinant expression of CPR was also shown to enhance CYP3A4-independent metabolisation of testosterone to androstenedione in CHO cells. We propose the novel serum-free CHO suspension cell lines with enhanced CPR and/or defined CYP activity as a promising “humanised” in vitro model to study the specific effects of those human CYPs. This could be relevant for toxicology and/or pharmacology studies in the pharmaceutical industry or medicine. KW - Chinese hamster ovary cells KW - CHO-K1 KW - CPR KW - CYP450 KW - cytochrome P450 monooxygenase KW - liver KW - NADPH P450 oxidoreductase KW - phase-1 biotransformation KW - serum-free KW - suspension cells Y1 - 2023 UR - https://www.mdpi.com/2073-4409/12/17/2140#metrics U6 - https://doi.org/10.3390/cells12172140 SN - 2073-4409 VL - 12 IS - 17 ER - TY - GEN A1 - Knauer, Jan Felix A1 - Schulz, Christian A1 - Zemella, Anne A1 - Wüstenhagen, Doreen A. A1 - Walter, Ruben Magnus A1 - Küpper, Jan-Heiner A1 - Kubick, Stefan T1 - Synthesis of mono Cytochrome P450 in a modified CHO-CPR cell-free protein production platform T2 - Scientific Reports N2 - AbstractCytochromes P450 (CYPs) are a group of monooxygenases that can be found in almost all kinds of organisms. For CYPs to receive electrons from co-substrate NADPH, the activity of NADPH-Cytochrome-P450-oxidoreductase (CPR) is required as well. In humans, CYPs are an integral part of liver-based phase-1 biotransformation, which is essential for the metabolization of multiple xenobiotics and drugs. Consequently, CYPs are important players during drug development and therefore these enzymes are implemented in diverse screening applications. For these applications it is usually advantageous to use mono CYP microsomes containing only the CYP of interest. The generation of mono-CYP containing mammalian cells and vesicles is difficult since endogenous CYPs are present in many cell types that contain the necessary co-factors. By obtaining translationally active lysates from a modified CHO-CPR cell line, it is now possible to generate mono CYPs in a cell-free protein synthesis process in a straightforward manner. As a proof of principle, the synthesis of active human CYPs from three different CYP450 gene families (CYP1A2, CYP2B6 and CYP3A4), which are of outstanding interest in industry and academia was demonstrated. Luciferase based activity assays confirm the activity of the produced CYPs and enable the individual adaptation of the synthesis process for efficient cell-free enzyme production. Furthermore, they allow for substrate and inhibitor screenings not only for wild-type CYPs but also for mutants and further CYP isoforms and variants. As an example, the turnover of selected CYP substrates by cell-free synthesized CYPs was demonstrated via an indirect luciferase assay-based screening setup. KW - Multidisciplinary Y1 - 2024 U6 - https://doi.org/10.1038/s41598-024-51781-6 SN - 2045-2322 VL - 14 ER -