@article{MuellerFinkeEbertetal.2018, author = {M{\"u}ller, S. M. and Finke, Hannah and Ebert, Franziska and Kopp, Johannes Florian and Schumacher, Fabian and Kleuser, Burkhard and Francesconi, Kevin A. and Raber, G. and Schwerdtle, Tanja}, title = {Arsenic-containing hydrocarbons}, series = {Archives of toxicology : official journal of EUROTOX}, volume = {92}, journal = {Archives of toxicology : official journal of EUROTOX}, number = {5}, publisher = {Springer}, address = {Heidelberg}, issn = {0340-5761}, doi = {10.1007/s00204-018-2194-z}, pages = {1751 -- 1765}, year = {2018}, abstract = {Arsenic-containing hydrocarbons (AsHCs), a subgroup of arsenolipids found in fish and algae, elicit substantial toxic effects in various human cell lines and have a considerable impact on cellular energy levels. The underlying mode of action, however, is still unknown. The present study analyzes the effects of two AsHCs (AsHC 332 and AsHC 360) on the expression of 44 genes covering DNA repair, stress response, cell death, autophagy, and epigenetics via RT-qPCR in human liver (HepG2) cells. Both AsHCs affected the gene expression, but to different extents. After treatment with AsHC 360, flap structure-specific endonuclease 1 (FEN1) as well as xeroderma pigmentosum group A complementing protein (XPA) and (cytosine-5)-methyltransferase 3A (DNMT3A) showed time- and concentration-dependent alterations in gene expression, thereby indicating an impact on genomic stability. In the subsequent analysis of epigenetic markers, within 72 h, neither AsHC 332 nor AsHC 360 showed an impact on the global DNA methylation level, whereas incubation with AsHC 360 increased the global DNA hydroxymethylation level. Analysis of cell extracts and cell media by HPLC-mass spectrometry revealed that both AsHCs were considerably biotransformed. The identified metabolites include not only the respective thioxo-analogs of the two AsHCs, but also several arsenic-containing fatty acids and fatty alcohols, contributing to our knowledge of biotransformation mechanisms of arsenolipids.}, language = {en} } @article{FinkeWandtEbertetal.2020, author = {Finke, Hannah and Wandt, Viktoria Klara Veronika and Ebert, Franziska and Guttenberger, Nikolaus and Glabonjat, Ronald A. and Stiboller, Michael and Francesconi, Kevin A. and Raber, Georg and Schwerdtle, Tanja}, title = {Toxicological assessment of arsenic-containing phosphatidylcholines in HepG2 cells}, volume = {12}, number = {7}, publisher = {Oxford University}, address = {Cambridge}, doi = {10.1039/d0mt00073f}, pages = {1159 -- 1170}, year = {2020}, abstract = {Arsenolipids include a wide range of organic arsenic species that occur naturally in seafood and thereby contribute to human arsenic exposure. Recently arsenic-containing phosphatidylcholines (AsPCs) were identified in caviar, fish, and algae. In this first toxicological assessment of AsPCs, we investigated the stability of both the oxo- and thioxo-form of an AsPC under experimental conditions, and analyzed cell viability, indicators of genotoxicity and biotransformation in human liver cancer cells (HepG2). Precise toxicity data could not be obtained owing to the low solubility in the cell culture medium of the thioxo-form, and the ease of hydrolysis of the oxo-form, and to a lesser degree the thioxo-form. Hydrolysis resulted amongst others in the respective constituent arsenic-containing fatty acid (AsFA). Incubation of the cells with oxo-AsPC resulted in a toxicity similar to that determined for the hydrolysis product oxo-AsFA alone, and there were no indices for genotoxicity. Furthermore, the oxo-AsPC was readily taken up by the cells resulting in high cellular arsenic concentrations (50 μM incubation: 1112 ± 146 μM As cellular), whereas the thioxo-AsPC was substantially less bioavailable (50 μM incubation: 293 ± 115 μM As cellular). Speciation analysis revealed biotransformation of the AsPCs to a series of AsFAs in the culture medium, and, in the case of the oxo-AsPC, to as yet unidentified arsenic species in cell pellets. The results reveal the difficulty of toxicity studies of AsPCs in vitro, indicate that their toxicity might be largely governed by their arsenic fatty acid content and suggest a multifaceted human metabolism of food derived complex arsenolipids.}, language = {en} } @article{FinkeWinkelbeinerLossowetal.2020, author = {Finke, Hannah and Winkelbeiner, Nicola Lisa and Lossow, Kristina and Hertel, Barbara and Wandt, Viktoria Klara Veronika and Schwarz, Maria and Pohl, Gabriele and Kopp, Johannes Florian and Ebert, Franziska and Kipp, Anna Patricia and Schwerdtle, Tanja}, title = {Effects of a Cumulative, Suboptimal Supply of Multiple Trace Elements in Mice}, series = {Molecular nutrition \& food research}, volume = {64}, journal = {Molecular nutrition \& food research}, number = {16}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {1613-4125}, doi = {10.1002/mnfr.202000325}, year = {2020}, abstract = {Scope: Trace element (TE) deficiencies often occur accumulated, as nutritional intake is inadequate for several TEs, concurrently. Therefore, the impact of a suboptimal supply of iron, zinc, copper, iodine, and selenium on the TE status, health parameters, epigenetics, and genomic stability in mice are studied. Methods and results: Male mice receive reduced or adequate amounts of TEs for 9 weeks. The TE status is analyzed mass-spectrometrically in serum and different tissues. Furthermore, gene and protein expression of TE biomarkers are assessed with focus on liver. Iron concentrations are most sensitive toward a reduced supply indicated by increased serum transferrin levels and altered hepatic expression of iron-related genes. Reduced TE supply results in smaller weight gain but higher spleen and heart weights. Additionally, inflammatory mediators in serum and liver are increased together with hepatic genomic instability. However, global DNA (hydroxy)methylation is unaffected by the TE modulation. Conclusion: Despite homeostatic regulation of most TEs in response to a low intake, this condition still has substantial effects on health parameters. It appears that the liver and immune system react particularly sensitive toward changes in TE intake. The reduced Fe status might be the primary driver for the observed effects.}, language = {en} }