@article{MaaresKeilKozaetal.2018,
  author    = {Maares, Maria and Keil, Claudia and Koza, Jenny and Straubing, Sophia and Schwerdtle, Tanja and Haase, Hajo},
  title     = {In Vitro Studies on Zinc Binding and Buffering by Intestinal Mucins},
  series = {International Journal of Molecular Sciences},
  volume    = {19},
  journal   = {International Journal of Molecular Sciences},
  number    = {9},
  issn      = {1422-0067},
  doi       = {10.3390/ijms19092662},
  pages     = {20},
  year      = {2018},
  abstract  = {The investigation of luminal factors influencing zinc availability and accessibility in the intestine is of great interest when analyzing parameters regulating intestinal zinc resorption. Of note, intestinal mucins were suggested to play a beneficial role in the luminal availability of zinc. Their exact zinc binding properties, however, remain unknown and the impact of these glycoproteins on human intestinal zinc resorption has not been investigated in detail. Thus, the aim of this study is to elucidate the impact of intestinal mucins on luminal uptake of zinc into enterocytes and its transfer into the blood. In the present study, in vitro zinc binding properties of mucins were analyzed using commercially available porcine mucins and secreted mucins of the goblet cell line HT-29-MTX. The molecular zinc binding capacity and average zinc binding affinity of these glycoproteins demonstrates that mucins contain multiple zinc-binding sites with biologically relevant affinity within one mucin molecule. Zinc uptake into the enterocyte cell line Caco-2 was impaired by zinc-depleted mucins. Yet this does not represent their form in the intestinal lumen in vivo under zinc adequate conditions. In fact, zinc-uptake studies into enterocytes in the presence of mucins with differing degree of zinc saturation revealed zinc buffering by these glycoproteins, indicating that mucin-bound zinc is still available for the cells. Finally, the impact of mucins on zinc resorption using three-dimensional cultures was studied comparing the zinc transfer of a Caco-2/HT-29-MTX co-culture and conventional Caco-2 monoculture. Here, the mucin secreting co-cultures yielded higher fractional zinc resorption and elevated zinc transport rates, suggesting that intestinal mucins facilitate the zinc uptake into enterocytes and act as a zinc delivery system for the intestinal epithelium.},
  language  = {en}
}
@article{DuyduBasaranAydinetal.2018,
  author    = {Duydu, Yalcin and Basaran, Nursen and Aydin, Sevtap and Ustundag, Aylin and Yalcin, Can {\"O}zg{\"u}r and Anlar, Hatice Gul and Bacanli, Merve and Aydos, Kaan and Atabekoglu, Cem Somer and Golka, Klaus and Ickstadt, Katja and Schwerdtle, Tanja and Werner, Matthias and Meyer, S{\"o}ren and Bolt, Hermann M.},
  title     = {Evaluation of FSH, LH, testosterone levels and semen parameters in male boron workers under extreme exposure conditions},
  series = {Archives of toxicology : official journal of EUROTOX},
  volume    = {92},
  journal   = {Archives of toxicology : official journal of EUROTOX},
  number    = {10},
  publisher = {Springer},
  address   = {Heidelberg},
  issn      = {0340-5761},
  doi       = {10.1007/s00204-018-2296-7},
  pages     = {3051 -- 3059},
  year      = {2018},
  abstract  = {Boric acid and sodium borates are currently classified in the EU-CLP regulation as "toxic to reproduction" under "Category 1B", with hazard statement of H360FD. However, so far field studies on male reproduction in China and in Turkey could not confirm such boron-associated toxic effects. As validation by another independent study is still required, the present study has investigated possible boron-associated effects on male reproduction in workers (n = 212) under different boron exposure conditions. The mean daily boron exposure (DBE) and blood boron concentration of workers in the extreme exposure group (n = 98) were 47.17 +/- 17.47 (7.95-106.8) mg B/day and 570.6 +/- 160.1 (402.6-1100) ng B/g blood, respectively. Nevertheless, boron-associated adverse effects on semen parameters, as well as on FSH, LH and total testosterone levels were not seen, even within the extreme exposure group. With this study, a total body of evidence has accumulated that allows to conclude that male reproductive effects are not relevant to humans, under any feasible and realistic conditions of exposure to inorganic boron compounds.},
  language  = {en}
}
@article{AlkerSchwerdtleSchomburgetal.2019,
  author    = {Alker, Wiebke and Schwerdtle, Tanja and Schomburg, Lutz and Haase, Hajo},
  title     = {A Zinpyr-1-based Fluorimetric Microassay for Free Zinc in Human Serum},
  series = {International journal of molecular sciences},
  volume    = {20},
  journal   = {International journal of molecular sciences},
  number    = {16},
  publisher = {MDPI},
  address   = {Basel},
  issn      = {1661-6596},
  doi       = {10.3390/ijms20164006},
  pages     = {13},
  year      = {2019},
  abstract  = {Zinc is an essential trace element, making it crucial to have a reliable biomarker for evaluating an individual's zinc status. The total serum zinc concentration, which is presently the most commonly used biomarker, is not ideal for this purpose, but a superior alternative is still missing. The free zinc concentration, which describes the fraction of zinc that is only loosely bound and easily exchangeable, has been proposed for this purpose, as it reflects the highly bioavailable part of serum zinc. This report presents a fluorescence-based method for determining the free zinc concentration in human serum samples, using the fluorescent probe Zinpyr-1. The assay has been applied on 154 commercially obtained human serum samples. Measured free zinc concentrations ranged from 0.09 to 0.42 nM with a mean of 0.22 ± 0.05 nM. It did not correlate with age or the total serum concentrations of zinc, manganese, iron or selenium. A negative correlation between the concentration of free zinc and total copper has been seen for sera from females. In addition, the free zinc concentration in sera from females (0.21 ± 0.05 nM) was significantly lower than in males (0.23 ± 0.06 nM). The assay uses a sample volume of less than 10 µL, is rapid and cost-effective and allows us to address questions regarding factors influencing the free serum zinc concentration, its connection with the body's zinc status, and its suitability as a future biomarker for an individual's zinc status.},
  language  = {en}
}
@article{WittEbertMeyeretal.2017,
  author    = {Witt, Barbara and Ebert, Franziska and Meyer, S{\"o}ren and Francesconi, Kevin A. and Schwerdtle, Tanja},
  title     = {Assessing neurodevelopmental effects of arsenolipids in pre-differentiated human neurons},
  series = {Molecular nutrition \& food research : bioactivity, chemistry, immunology, microbiology, safety, technology},
  volume    = {61},
  journal   = {Molecular nutrition \& food research : bioactivity, chemistry, immunology, microbiology, safety, technology},
  publisher = {Wiley},
  address   = {Hoboken},
  issn      = {1613-4125},
  doi       = {10.1002/mnfr.201700199},
  pages     = {10},
  year      = {2017},
  abstract  = {Scope: In the general population exposure to arsenic occurs mainly via diet. Highest arsenic concentrations are found in seafood, where arsenic is present predominantly in its organic forms including arsenolipids. Since recent studies have provided evidence that arsenolipids could reach the brain of an organism and exert toxicity in fully differentiated human neurons, this work aims to assess the neurodevelopmental toxicity of arsenolipids. Methods and results: Neurodevelopmental effects of three arsenic-containing hydrocarbons (AsHC), two arsenic-containing fatty acids (AsFA), arsenite and dimethylarsinic acid (DMA(V)) were characterized in pre-differentiated human neurons. AsHCs and arsenite caused substantial cytotoxicity in a similar, low concentration range, whereas AsFAs and DMA(V) were less toxic. AsHCs were highly accessible for cells and exerted pronounced neurodevelopmental effects, with neurite outgrowth and the mitochondrial membrane potential being sensitive endpoints; arsenite did not substantially decrease those two endpoints. In fully differentiated neurons, arsenite and AsHCs caused neurite toxicity. Conclusion: These results indicate for a neurodevelopmental potential of AsHCs. Taken into account the possibility that AsHCs might easily reach the developing brain when exposed during early life, neurotoxicity and neurodevelopmental toxicity cannot be excluded. Further studies are needed in order to progress the urgently needed risk assessment.},
  language  = {en}
}
@article{WittMeyerEbertetal.2017,
  author    = {Witt, Barbara and Meyer, S{\"o}ren and Ebert, Franziska and Francesconi, Kevin A. and Schwerdtle, Tanja},
  title     = {Toxicity of two classes of arsenolipids and their water-soluble metabolites in human differentiated neurons},
  series = {Archives of toxicology : official journal of EUROTOX},
  volume    = {91},
  journal   = {Archives of toxicology : official journal of EUROTOX},
  publisher = {Springer},
  address   = {Heidelberg},
  issn      = {0340-5761},
  doi       = {10.1007/s00204-017-1933-x},
  pages     = {3121 -- 3134},
  year      = {2017},
  abstract  = {Arsenolipids are lipid-soluble organoarsenic compounds, mainly occurring in marine organisms, with arsenic-containing hydrocarbons (AsHCs) and arsenic-containing fatty acids (AsFAs) representing two major subgroups. Recently, toxicity studies of several arsenolipids showed a high cytotoxic potential of those arsenolipids in human liver and bladder cells. Furthermore, feeding studies with Drosophila melanogaster indicated an accumulation of arsenolipids in the fruit fly's brain. In this study, the neurotoxic potential of three AsHCs, two AsFAs and three metabolites (dimethylarsinic acid, thio/oxo-dimethylarsenopropanoic acid) was investigated in comparison to the toxic reference arsenite (iAsIII) in fully differentiated human brain cells (LUHMES cells). Thereby, in the case of AsHCs both the cell number and cell viability were reduced in a low micromolar concentration range comparable to iAsIII, while AsFAs and the applied metabolites were less toxic. Mechanistic studies revealed that AsHCs reduced the mitochondrial membrane potential, whereas neither iAsIII nor AsFAs had an impact. Furthermore, neurotoxic mechanisms were investigated by examining the neuronal network. Here, AsHCs massively disturbed the neuronal network and induced apoptotic effects, while iAsIII and AsFAs showed comparatively lesser effects. Taking into account the substantial in vitro neurotoxic potential of the AsHCs and the fact that they could transfer across the physiological barriers of the brain, a neurotoxic potential in vivo for the AsHCs cannot be excluded and needs to be urgently characterized.},
  language  = {en}
}
@article{LossowSchwerdtleKipp2019,
  author    = {Lossow, Kristina and Schwerdtle, Tanja and Kipp, Anna Patricia},
  title     = {Selen und Jod: essenzielle Spurenelemente f{\"u}r die Schilddr{\"u}se},
  series = {Ern{\"a}hrungs-Umschau : Forschung \& Praxis},
  volume    = {66},
  journal   = {Ern{\"a}hrungs-Umschau : Forschung \& Praxis},
  number    = {9},
  publisher = {Umschau-Zeitschriftenverl.},
  address   = {Frankfurt, Main},
  issn      = {0174-0008},
  doi       = {10.4455/eu.2019.032},
  pages     = {M531 -- M536},
  year      = {2019},
  abstract  = {Selen und Jod sind essenzielle Spurenelemente, die gemeinsam f{\"u}r eine optimale Funktionst{\"u}chtigkeit der Schilddr{\"u}se erforderlich sind. Der Mangel eines oder beider Elemente f{\"u}hrt zu Verschiebungen auf Ebene der Schilddr{\"u}senhormonproduktion mit weitreichenden Konsequenzen f{\"u}r Stoffwechselprozesse, neurologische Entwicklung und Erkrankungen. Auch bei Autoimmunerkrankungen der Schilddr{\"u}se spielt die Versorgung mit Jod und Selen eine wichtige Rolle. Als Biomarker f{\"u}r den Selenstatus eignet sich der Gehalt des Gesamtselens oder der des Selenoproteins P im Serum. Zur Bestimmung des Jodstatus wird in der Regel der Jodgehalt im Urin herangezogen. Um den Versorgungszustand an diesen und vier weiteren essenziellen Spurenelementen besser zu erfassen, charakterisiert die Forschungsgruppe TraceAge alters- und geschlechtsspezifische Spurenelementprofile und neue funktionelle Biomarker der einzelnen Spurenelemente. Außerdem sollen Interaktionen weiterer Spurenelemente genauer untersucht werden.},
  language  = {de}
}
@article{MeyerMatissekMuelleretal.2014,
  author    = {Meyer, S{\"o}ren and Matissek, M. and M{\"u}ller, Sandra Marie and Taleshi, M. S. and Ebert, Franziska and Francesconi, Kevin A. and Schwerdtle, Tanja},
  title     = {In vitro toxicological characterisation of three arsenic-containing hydrocarbons},
  series = {Metallomics},
  volume    = {2014},
  journal   = {Metallomics},
  number    = {6},
  issn      = {1756-591X},
  doi       = {10.1039/c4mt00061g},
  pages     = {1023 -- 1033},
  year      = {2014},
  abstract  = {Arsenic-containing hydrocarbons are one group of fat-soluble organic arsenic compounds (arsenolipids) found in marine fish and other seafood. A risk assessment of arsenolipids is urgently needed, but has not been possible because of the total lack of toxicological data. In this study the cellular toxicity of three arsenic-containing hydrocarbons was investigated in cultured human bladder (UROtsa) and liver (HepG2) cells. Cytotoxicity of the arsenic-containing hydrocarbons was comparable to that of arsenite, which was applied as the toxic reference arsenical. A large cellular accumulation of arsenic, as measured by ICP-MS/MS, was observed after incubation of both cell lines with the arsenolipids. Moreover, the toxic mode of action shown by the three arsenic-containing hydrocarbons seemed to differ from that observed for arsenite. Evidence suggests that the high cytotoxic potential of the lipophilic arsenicals results from a decrease in the cellular energy level. This first in vitro based risk assessment cannot exclude a risk to human health related to the presence of arsenolipids in seafood, and indicates the urgent need for further toxicity studies in experimental animals to fully assess this possible risk.},
  language  = {en}
}
@article{UnterbergLeffersHuebneretal.2014,
  author    = {Unterberg, Marlies and Leffers, Larissa and H{\"u}bner, Florian and Humpf, Hans-Ulrich and Lepikhov, Konstantin and Walter, J{\"o}rn and Ebert, Franziska and Schwerdtle, Tanja},
  title     = {Toxicity of arsenite and thio-DMAV after long-term (21 days) incubation of human urothelial cells: cytotoxicity, genotoxicity and epigenetics},
  series = {Toxicology Research},
  volume    = {3},
  journal   = {Toxicology Research},
  number    = {6},
  publisher = {Royal Society of Chemistry},
  address   = {Cambridge},
  issn      = {2045-4538},
  pages     = {456 -- 464},
  year      = {2014},
  abstract  = {This study aims to further mechanistically understand toxic modes of action after chronic inorganic arsenic exposure. Therefore long-term incubation studies in cultured cells were carried out, to display chronically attained changes, which cannot be observed in the generally applied in vitro short-term incubation studies. Particularly, the cytotoxic, genotoxic and epigenetic effects of an up to 21 days incubation of human urothelial (UROtsa) cells with pico- to nanomolar concentrations of iAsIII and its metabolite thio-DMAV were compared. After 21 days of incubation, cytotoxic effects were strongly enhanced in the case of iAsIII and might partly be due to glutathione depletion and genotoxic effects on the chromosomal level. These results are in strong contrast to cells exposed to thio-DMAV. Thus, cells seemed to be able to adapt to this arsenical, as indicated among others by an increase in the cellular glutathione level. Most interestingly, picomolar concentrations of both iAsIII and thio-DMAV caused global DNA hypomethylation in UROtsa cells, which was quantified in parallel by 5-medC immunostaining and a newly established, reliable, high resolution mass spectrometry (HRMS)-based test system. This is the first time that epigenetic effects are reported for thio-DMAV; iAsIII induced epigenetic effects occur in at least 8000 fold lower concentrations as reported in vitro before. The fact that both arsenicals cause DNA hypomethylation at really low, exposure-relevant concentrations in human urothelial cells suggests that this epigenetic effect might contribute to inorganic arsenic induced carcinogenicity, which for sure has to be further investigated in future studies.},
  language  = {en}
}
@article{MeyerRaberEbertetal.2015,
  author    = {Meyer, S. and Raber, G. and Ebert, Franziska and Leffers, L. and M{\"u}ller, Sandra Marie and Taleshi, M. S. and Francesconi, Kevin A. and Schwerdtle, Tanja},
  title     = {In vitro toxicological characterisation of arsenic-containing fatty acids and three of their metabolites},
  series = {Toxicology research},
  volume    = {5},
  journal   = {Toxicology research},
  number    = {4},
  publisher = {Royal Society of Chemistry},
  address   = {Cambridge},
  issn      = {2045-4538},
  doi       = {10.1039/c5tx00122f},
  pages     = {1289 -- 1296},
  year      = {2015},
  abstract  = {Arsenic-containing fatty acids are a group of fat-soluble arsenic species (arsenolipids) which are present in marine fish and other seafood. Recently, it has been shown that arsenic-containing hydrocarbons, another group of arsenolipids, exert toxicity in similar concentrations comparable to arsenite although the toxic modes of action differ. Hence, a risk assessment of arsenolipids is urgently needed. In this study the cellular toxicity of a saturated (AsFA 362) and an unsaturated (AsFA 388) arsenic-containing fatty acid and three of their proposed metabolites (DMAV, DMAPr and thio-DMAPr) were investigated in human liver cells (HepG2). Even though both arsenic-containing fatty acids were less toxic as compared to arsenic-containing hydrocarbons and arsenite, significant effects were observable at μM concentrations. DMAV causes effects in a similar concentration range and it could be seen that it is metabolised to its highly toxic thio analogue thio-DMAV in HepG2 cells. Nevertheless, DMAPr and thio-DMAPr did not exert any cytotoxicity. In summary, our data indicate that risks to human health related to the presence of arsenic-containing fatty acids in marine food cannot be excluded. This stresses the need for a full in vitro and in vivo toxicological characterisation of these arsenolipids.},
  language  = {en}
}
@article{ZhouPanZhangetal.2020,
  author    = {Zhou, Suqiong and Pan, Yuanwei and Zhang, Jianguang and Li, Yan and Neumann, Falko and Schwerdtle, Tanja and Li, Wenzhong and Haag, Rainer},
  title     = {Dendritic polyglycerol-conjugated gold nanostars with different densities of functional groups to regulate osteogenesis in human mesenchymal stem cells},
  series = {Nanoscale},
  volume    = {12},
  journal   = {Nanoscale},
  number    = {47},
  publisher = {Royal Society of Chemistry},
  address   = {Cambridge},
  issn      = {2040-3364},
  doi       = {10.1039/d0nr06570f},
  pages     = {24006 -- 24019},
  year      = {2020},
  abstract  = {Nanomaterials play an important role in mimicking the biochemical and biophysical cues of the extracellular matrix in human mesenchymal stem cells (MSCs). Increasing studies have demonstrated the crucial impact of functional groups on MSCs, while limited research is available on how the functional group's density on nanoparticles regulates MSC behavior. Herein, the effects of dendritic polyglycerol (dPG)-conjugated gold nanostars (GNSs) with different densities of functional groups on the osteogenesis of MSCs are systematically investigated. dPG@GNS nanocomposites have good biocompatibility and the uptake by MSCs is in a functional group density-dependent manner. The osteogenic differentiation of MSCs is promoted by all dPG@GNS nanocomposites, in terms of alkaline phosphatase activity, calcium deposition, and expression of osteogenic protein and genes. Interestingly, the dPGOH@GNSs exhibit a slight upregulation in the expression of osteogenic markers, while the different charged densities of sulfate and amino groups show more efficacy in the promotion of osteogenesis. Meanwhile, the sulfated nanostars dPGS20@GNSs show the highest enhancement. Furthermore, various dPG@GNS nanocomposites exerted their effects by regulating the activation of Yes-associated protein (YAP) to affect osteogenic differentiation. These results indicate that dPG@GNS nanocomposites have functional group density-dependent influence on the osteogenesis of MSCs, which may provide a new insight into regulating stem cell fate.},
  language  = {en}
}
@article{TaylorGoodaleRaabetal.2017,
  author    = {Taylor, Vivien and Goodale, Britton and Raab, Andrea and Schwerdtle, Tanja and Reimer, Ken and Conklin, Sean and Karagas, Margaret R. and Francesconi, Kevin A.},
  title     = {Human exposure to organic arsenic species from seafood},
  series = {The science of the total environment : an international journal for scientific research into the environment and its relationship with man},
  volume    = {580},
  journal   = {The science of the total environment : an international journal for scientific research into the environment and its relationship with man},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0048-9697},
  doi       = {10.1016/j.scitotenv.2016.12.113},
  pages     = {266 -- 282},
  year      = {2017},
  abstract  = {Seafood, including finfish, shellfish, and seaweed, is the largest contributor to arsenic (As) exposure in many human populations. In contrast to the predominance of inorganic As in water and many terrestrial foods, As in marine-derived foods is present primarily in the form of organic compounds. To date, human exposure and toxicological assessments have focused on inorganic As, while organic As has generally been considered to be nontoxic. However, the high concentrations of organic As in seafood, as well as the often complex As speciation, can lead to complications in assessing As exposure from diet. In this report, we evaluate the presence and distribution of organic As species in seafood, and combined with consumption data, address the current capabilities and needs for determining human exposure to these compounds. The analytical approaches and shortcomings for assessing these compounds are reviewed, with a focus on the best practices for characterization and quantitation. Metabolic pathways and toxicology of two important classes of organic arsenicals, arsenolipids and arsenosugars, are examined, as well as individual variability in absorption of these compounds. Although determining health outcomes or assessing a need for regulatory policies for organic As exposure is premature, the extensive consumption of seafood globally, along with the preliminary toxicological profiles of these compounds and their confounding effect on assessing exposure to inorganic As, suggests further investigations and process-level studies on organic As are needed to fill the current gaps in knowledge.},
  language  = {en}
}
@article{EbertZiemannWandtetal.2020,
  author    = {Ebert, Franziska and Ziemann, Vanessa and Wandt, Viktoria Klara Veronika and Witt, Barbara and M{\"u}ller, Sandra Marie and Guttenberger, Nikolaus and Bankoglu, Ezgi Eyluel and Stopper, Helga and Raber, Georg and Francesconi, Kevin A. and Schwerdtle, Tanja},
  title     = {Cellular toxicological characterization of a thioxolated arsenic-containing hydrocarbon},
  series = {Journal of trace elements in medicine and biology},
  volume    = {61},
  journal   = {Journal of trace elements in medicine and biology},
  publisher = {Elsevier},
  address   = {M{\"u}nchen},
  doi       = {10.1016/j.jtemb.2020.126563},
  year      = {2020},
  abstract  = {Arsenolipids, especially arsenic-containing hydrocarbons (AsHC), are an emerging class of seafood originating contaminants. Here we toxicologically characterize a recently identified oxo-AsHC 332 metabolite, thioxo-AsHC 348 in cultured human liver (HepG2) cells. Compared to results of previous studies of the parent compound oxo-AsHC 332, thioxo-AsHC 348 substantially affected cell viability in the same concentration range but exerted about 10-fold lower cellular bioavailability. Similar to oxo-AsHC 332, thioxo-AsHC 348 did not substantially induce oxidative stress nor DNA damage. Moreover, in contrast to oxo-AsHC 332 mitochondria seem not to be a primary subcellular toxicity target for thioxo-AsHC 348. This study indicates that thioxo-AsHC 348 is at least as toxic as its parent compound oxo-AsHC 332 but very likely acts via a different mode of toxic action, which still needs to be identified.},
  language  = {en}
}
@article{MaaresDumanKeiletal.2018,
  author    = {Maares, Maria and Duman, Ayse and Keil, Claudia and Schwerdtle, Tanja and Haase, Hajo},
  title     = {The impact of apical and basolateral albumin on intestinal zinc resorption in the Caco-2/HT-29-MTX co-culture model},
  series = {Metallomics : integrated biometal science},
  volume    = {10},
  journal   = {Metallomics : integrated biometal science},
  number    = {7},
  publisher = {Royal Society of Chemistry},
  address   = {Cambridge},
  issn      = {1756-5901},
  doi       = {10.1039/c8mt00064f},
  pages     = {979 -- 991},
  year      = {2018},
  abstract  = {The molecular mechanisms of intestinal zinc resorption and its regulation are still topics of ongoing research. To this end, the application of suitable in vitro intestinal models, optimized with regard to their cellular composition and medium constituents, is of crucial importance. As one vital aspect, the impact of cell culture media or buffer compounds, respectively, on the speciation and cellular availability of zinc has to be considered when investigating zinc resorption. Thus, the present study aims to investigate the impact of serum, and in particular its main constituent serum albumin, on zinc uptake and toxicity in the intestinal cell line Caco-2. Furthermore, the impact of serum albumin on zinc resorption is analyzed using a co-culture of Caco-2 cells and the mucin-producing goblet cell line HT-29-MTX. Apically added albumin significantly impaired zinc uptake into enterocytes and buffered its cytotoxicity. Yet, undigested albumin does not occur in the intestinal lumen in vivo and impairment of zinc uptake was abrogated by digestion of albumin. Interestingly, zinc uptake, as well as gene expression studies of mt1a and selected intestinal zinc transporters after zinc incubation for 24 h, did not show significant differences between 0 and 10\% serum. Importantly, the basolateral application of serum in a transport study significantly enhanced fractional apical zinc resorption, suggesting that the occurrence of a zinc acceptor in the plasma considerably affects intestinal zinc resorption. This study demonstrates that the apical and basolateral medium composition is crucial when investigating zinc, particularly its intestinal resorption, using in vitro cell culture.},
  language  = {en}
}
@article{DuyduBasaranUstundagetal.2018,
  author    = {Duydu, Yalcin and Basaran, Nursen and Ustundag, Aylin and Aydin, Sevtap and Yalcin, Can Ozgur and Anlar, Hatice Gul and Bacanli, Merve and Aydos, Kaan and Atabekoglu, Cem Somer and Golka, Klaus and Ickstadt, Katja and Schwerdtle, Tanja and Werner, Matthias and Meyer, S{\"o}ren and Bolt, Hermann M.},
  title     = {Birth weights of newborns and pregnancy outcomes of environmentally boron-exposed females in Turkey},
  series = {Archives of toxicology : official journal of EUROTOX},
  volume    = {92},
  journal   = {Archives of toxicology : official journal of EUROTOX},
  number    = {8},
  publisher = {Springer},
  address   = {Heidelberg},
  issn      = {0340-5761},
  doi       = {10.1007/s00204-018-2238-4},
  pages     = {2475 -- 2485},
  year      = {2018},
  abstract  = {Boric acid and sodium borates are currently classified as being toxic to reproduction under "Category 1B" with the hazard statement of "H360 FD" in the European CLP regulation. This has prompted studies on boron-mediated reprotoxic effects in male workers in boron mining areas and boric acid production plants. By contrast, studies on boron-mediated developmental effects in females are scarce. The present study was designed to fill this gap. Hundred and ninety nine females residing in Bandirma and Bigadic participated in this study investigating pregnancy outcomes. The participants constituted a study group covering blood boron from low (< 100 ng B/g blood, n = 143) to high (> 150 ng B/g blood, n = 27) concentrations. The mean blood boron concentration and the mean estimated daily boron exposure of the high exposure group was 274.58 (151.81-975.66) ng B/g blood and 24.67 (10.47-57.86) mg B/day, respectively. In spite of the high level of daily boron exposure, boron-mediated adverse effects on induced abortion, spontaneous abortion (miscarriage), stillbirth, infant death, neonatal death, early neonatal death, preterm birth, congenital anomalies, sex ratio and birth weight of newborns were not observed.},
  language  = {en}
}
@article{TurriniKroepflJensenetal.2018,
  author    = {Turrini, Nikolaus G. and Kroepfl, Nina and Jensen, Kenneth Bendix and Reiter, Tamara C. and Francesconi, Kevin A. and Schwerdtle, Tanja and Kroutil, Wolfgang and Kuehnelt, Doris},
  title     = {Biosynthesis and isolation of selenoneine from genetically modified fission yeast},
  series = {Metallomics : integrated biometal science},
  volume    = {10},
  journal   = {Metallomics : integrated biometal science},
  number    = {10},
  publisher = {Royal Society of Chemistry},
  address   = {Cambridge},
  issn      = {1756-5901},
  doi       = {10.1039/c8mt00200b},
  pages     = {1532 -- 1538},
  year      = {2018},
  abstract  = {Selenoneine, a naturally occurring form of selenium, is the selenium analogue of ergothioneine, a sulfur species with health relevance not only as a purported antioxidant but likely also beyond. Selenoneine has been speculated to exhibit similar effects. To study selenoneine's health properties as well as its metabolic transformation, the pure compound is required. Chemical synthesis of selenoneine, however, is challenging and biosynthetic approaches have been sought. We herein report the biosynthesis and isolation of selenoneine from genetically modified fission yeast Schizosaccharomyces pombe grown in a medium containing sodium selenate. After cell lysis and extraction with methanol, selenoneine was purified by three consecutive preparative reversed-phase HPLC steps. The product obtained at the mg level was characterised by high resolution mass spectrometry, NMR and HPLC/ICPMS. Biosynthesis was found to be a promising alternative to chemical synthesis, and should be suitable for upscaling to produce higher amounts of this important selenium species in the future.},
  language  = {en}
}
@article{KoppMuellerPohletal.2019,
  author    = {Kopp, Johannes Florian and M{\"u}ller, Sandra Marie and Pohl, Gabriele and Lossow, Kristina and Kipp, Anna Patricia and Schwerdtle, Tanja},
  title     = {A quick and simple method for the determination of six trace elements in mammalian serum samples using ICP-MS/MS},
  series = {Journal of trace elements in medicine and biology},
  volume    = {54},
  journal   = {Journal of trace elements in medicine and biology},
  publisher = {Elsevier},
  address   = {M{\"u}nchen},
  issn      = {0946-672X},
  doi       = {10.1016/j.jtemb.2019.04.015},
  pages     = {221 -- 225},
  year      = {2019},
  abstract  = {In order to assess the individual trace element status of humans for either medical or scientific purposes, amongst others, blood serum levels are determined. Furthermore, animal models are used to study interactions of trace elements. Most published methods require larger amounts (500-1000 mu L) of serum to achieve a reliable determination of multiple trace elements. However, oftentimes, these amounts of serum cannot be dedicated to a single analysis and the amount available for TE-determination is much lower. Therefore, a published ICP-MS/MS method for trace element determination in serum was miniaturized, optimized and validated for the measurement of Mn, Fe, Cu Zn, I and Se in as little as 50 mu L of human and murine serum and is presented in this work. For validation, recoveries of multiple LOTs and levels from commercially available human reference serum samples were determined, infra- and inter-day variations were assessed and limits of detection and quantification determined. It is shown, that the method is capable of giving accurate and reproducible results for all six elements within the relevant concentration ranges for samples from humans living in central Europe as well as from laboratory mice. As a highlight, the achieved limits of detection and quantification for Mn were found to be at 0.02 mu g/L serum and 0.05 mu g/L serum, respectively, while using an alkaline diluent for the parallel determination of iodine.},
  language  = {en}
}
@article{BasaranDuyduUstundagetal.2019,
  author    = {Basaran, Nursen and Duydu, Yalcin and Ustundag, Aylin and Taner, Gokce and Aydin, Sevtap and Anlar, Hatice Gul and Yalcin, Can {\"O}zg{\"u}r and Bacanli, Merve and Aydos, Kaan and Atabekoglu, Cem Somer and Golka, Klaus and Ickstadt, Katja and Schwerdtle, Tanja and Werner, Matthias and Meyer, S{\"o}ren and Bolt, Hermann M.},
  title     = {Evaluation of the DNA damage in lymphocytes, sperm and buccal cells of workers under environmental and occupational boron exposure conditions},
  series = {Mutation Research/Genetic Toxicology and Environmental Mutagenesis},
  volume    = {843},
  journal   = {Mutation Research/Genetic Toxicology and Environmental Mutagenesis},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {1383-5718},
  doi       = {10.1016/j.mrgentox.2018.12.013},
  pages     = {33 -- 39},
  year      = {2019},
  abstract  = {Industrial production and use of boron compounds have increased during the last decades, especially for the manufacture of borosilicate glass, fiberglass, metal alloys and flame retardants. This study was conducted in two districts of Balikesir; Bandirma and Bigadic, which geographically belong to the Marmara Region of Turkey. Bandirma is the production and exportation zone for the produced boric acid and some borates and Bigadic has the largest B deposits in Turkey. 102 male workers who were occupationally exposed to boron from Bandirma and 110 workers who were occupationally and environmentally exposed to boron from Bigadic participated to our study. In this study the DNA damage in the sperm, blood and buccal cells of 212 males was evaluated by comet and micronucleus assays. No significant increase in the DNA damage in blood, sperm and buccal cells was observed in the residents exposed to boron both occupationally and environmentally (p = 0.861) for Comet test in the sperm samples, p = 0.116 for Comet test in the lymphocyte samples, p = 0.042 for micronucleus (MN) test, p = 0.955 for binucleated cells (BN), p = 1.486 for condensed chromatin (CC), p = 0.455 for karyorrhectic cells (KHC), p = 0.541 for karyolitic cells (KLY), p = 1.057 for pyknotic cells (PHC), p = 0.331 for nuclear bud (NBUD)). No correlations were seen between blood boron levels and tail intensity values of the sperm samples, lymphocyte samples, frequencies of MN, BN, KHC, KYL, PHC and NBUD. The results of this study came to the same conclusions of the previous studies that boron does not induce DNA damage even under extreme exposure conditions.},
  language  = {en}
}
@article{LiSchlaichKulkaetal.2019,
  author    = {Li, Mingjun and Schlaich, Christoph and Kulka, Michael Willem and Donskyi, Ievgen S. and Schwerdtle, Tanja and Unger, Wolfgang E. S. and Haag, Rainer},
  title     = {Mussel-inspired coatings with tunable wettability, for enhanced antibacterial efficiency and reduced bacterial adhesion},
  series = {Journal of materials chemistry : B, Materials for biology and medicine},
  volume    = {7},
  journal   = {Journal of materials chemistry : B, Materials for biology and medicine},
  number    = {21},
  publisher = {Royal Society of Chemistry},
  address   = {Cambridge},
  issn      = {2050-750X},
  doi       = {10.1039/c9tb00534j},
  pages     = {3438 -- 3445},
  year      = {2019},
  abstract  = {Over the last few decades, there has been a tremendous increase in research on antibacterial surface coatings as an alternative strategy against bacterial infections. Although there are several examples of effective strategies to prevent bacterial adhesion, the effect of the wetting properties on the coating was rarely considered as a crucial factor. Here we report an in-depth study on the effect of extreme wettability on the antibacterial efficiency of a silver nanoparticles ( AgNPs)-based coating. By controlling surface polymerization of mussel-inspired dendritic polyglycerol ( MI-dPG) and post-functionalization, surfaces with wetting properties ranging from superhydrophilic to superhydrophobic were fabricated. Subsequently, AgNPs were embedded into the coatings by applying in situ reduction using the free catechols-moieties present in the MI-dPG coating. The resulting polymer coatings exhibited excellent antibacterial ability against planktonic Escherichia coli ( E. coli) DH5a and Staphylococcus aureus ( S. aureus) SH1000. The antibacterial efficiency of the coatings was analyzed by using inductively coupled plasma mass spectrometry ( ICP-MS) and bacterial viability tests. Furthermore, the antifouling properties of the coatings in relation to the antibacterial properties were evaluated.},
  language  = {en}
}
@article{MeyerLopezSerranoMitzeetal.2017,
  author    = {Meyer, S{\"o}ren and Lopez-Serrano, Aniceto and Mitze, Hanna and Jakubowski, Norbert and Schwerdtle, Tanja},
  title     = {Single-cell analysis by ICP-MS/MS as a fast tool for cellular bioavailability studies of arsenite},
  series = {Metallomics : integrated biometal science},
  volume    = {10},
  journal   = {Metallomics : integrated biometal science},
  number    = {1},
  publisher = {Royal Society of Chemistry},
  address   = {Cambridge},
  issn      = {1756-5901},
  doi       = {10.1039/c7mt00285h},
  pages     = {73 -- 76},
  year      = {2017},
  abstract  = {Single-cell inductively coupled plasma mass spectrometry (SC-ICP-MS) has become a powerful and fast tool to evaluate the elemental composition at a single-cell level. In this study, the cellular bioavailability of arsenite (incubation of 25 and 50 mu M for 0-48 h) has been successfully assessed by SC-ICP-MS/MS for the first time directly after re-suspending the cells in water. This procedure avoids the normally arising cell membrane permeabilization caused by cell fixation methods (e.g. methanol fixation). The reliability and feasibility of this SC-ICP-MS/MS approach with a limit of detection of 0.35 fg per cell was validated by conventional bulk ICP-MS/MS analysis after cell digestion and parallel measurement of sulfur and phosphorus.},
  language  = {en}
}
@article{KroepflMarschallFrancesconietal.2017,
  author    = {Kr{\"o}pfl, Nina and Marschall, Talke A. and Francesconi, Kevin A. and Schwerdtle, Tanja and Kuehnelt, Doris},
  title     = {Quantitative determination of the sulfur-containing antioxidant ergothioneine by HPLC/ICP- QQQ-MS},
  series = {Journal of Analytical Atomic Spectrometry},
  volume    = {32},
  journal   = {Journal of Analytical Atomic Spectrometry},
  publisher = {Royal Society of Chemistry},
  address   = {Cambridge},
  issn      = {0267-9477},
  doi       = {10.1039/c7ja00030h},
  pages     = {1571 -- 1581},
  year      = {2017},
  abstract  = {Interest in the sulfur-containing antioxidant ergothioneine calls for reliable analytical methods for its quantification. In this work, a method based on reversed-phase high performance liquid chromatography (RP-HPLC) coupled with elemental mass spectrometry detection in mass shift mode (inductively coupled plasma triple quadrupole mass spectrometry, ICP-QQQ-MS) using oxygen as the reaction gas was developed for the element-selective determination of ergothioneine in complex biological matrices. Application of an instrumental setup using a 6-port-valve and the introduction of a methanol gradient allowed the time-efficient analysis of samples containing strongly retained sulfur species besides ergothioneine without compromising ICPMS detection. In aqueous solution, limits of detection and quantification (LOD and LOQ) of the optimized method for m/z 32 -> 48 (SO+) were 0.23 mu g S per L and 0.80 mu g S per L, respectively; measurements in a complex matrix (human hepatocyte carcinoma cells, HepG2) resulted in an LOD of 0.6 mu g S per L and an LOQ of 2.3 mu g S per L. Recoveries of ergothioneine from cell pellets spiked with the analyte before cell lysis (97 +/- 3\%) matched those obtained for cell culture medium spiked before syringe filtration (96 +/- 9\%) demonstrating that sample preparation did not impair the quantitative determination of ergothioneine. When HepG2 cells were exposed to ergothioneine via the culture medium, they showed low absorption; approximately 3\% of the added ergothioneine was found in cell lysates, while most of it (>= 85\%) remained in the cell culture medium. The method is capable of separating ergothioneine from other biologically relevant sulfur-containing species and is expected to be of broad future use. Furthermore, the potential use for the simultaneous separation of selenium species, thereby extending the scope of possible applications, was demonstrated by applying it to water extracts of oyster mushrooms.},
  language  = {en}
}