@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{HauffeRathAgyapongetal.2022, author = {Hauffe, Robert and Rath, Michaela and Agyapong, Wilson and Jonas, Wenke and Vogel, Heike and Schulz, Tim Julius and Schwarz, Maria and Kipp, Anna Patricia and Bl{\"u}her, Matthias and Kleinridders, Andr{\´e}}, title = {Obesity Hinders the Protective Effect of Selenite Supplementation on Insulin Signaling}, series = {Antioxidants}, volume = {11}, journal = {Antioxidants}, edition = {5}, publisher = {MDPI}, address = {Basel, Schweiz}, issn = {2076-3921}, doi = {10.3390/antiox11050862}, pages = {1 -- 16}, year = {2022}, abstract = {The intake of high-fat diets (HFDs) containing large amounts of saturated long-chain fatty acids leads to obesity, oxidative stress, inflammation, and insulin resistance. The trace element selenium, as a crucial part of antioxidative selenoproteins, can protect against the development of diet-induced insulin resistance in white adipose tissue (WAT) by increasing glutathione peroxidase 3 (GPx3) and insulin receptor (IR) expression. Whether selenite (Se) can attenuate insulin resistance in established lipotoxic and obese conditions is unclear. We confirm that GPX3 mRNA expression in adipose tissue correlates with BMI in humans. Cultivating 3T3-L1 pre-adipocytes in palmitate-containing medium followed by Se treatment attenuates insulin resistance with enhanced GPx3 and IR expression and adipocyte differentiation. However, feeding obese mice a selenium-enriched high-fat diet (SRHFD) only resulted in a modest increase in overall selenoprotein gene expression in WAT in mice with unaltered body weight development, glucose tolerance, and insulin resistance. While Se supplementation improved adipocyte morphology, it did not alter WAT insulin sensitivity. However, mice fed a SRHFD exhibited increased insulin content in the pancreas. Overall, while selenite protects against palmitate-induced insulin resistance in vitro, obesity impedes the effect of selenite on insulin action and adipose tissue metabolism in vivo.}, language = {en} } @phdthesis{Kipp2014, author = {Kipp, Anna Patricia}, title = {Physiologische und Tumor-Assoziierte Funktionen von Selen und Selenoproteinen}, pages = {IV, 198}, year = {2014}, language = {de} } @misc{MuellerDawczynskiWiestetal.2020, author = {M{\"u}ller, Sandra and Dawczynski, Christine and Wiest, Johanna and Lorkowski, Stefan and Kipp, Anna Patricia and Schwerdtle, Tanja}, title = {Functional Biomarkers for the Selenium Status in a Human Nutritional Intervention Study}, series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, number = {878}, issn = {1866-8372}, doi = {10.25932/publishup-46011}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-460115}, pages = {16}, year = {2020}, abstract = {Soils in Germany are commonly low in selenium; consequently, a sufficient dietary supply is not always ensured. The extent of such provision adequacy is estimated by the optimal effect range of biomarkers, which often reflects the physiological requirement. Preceding epidemiological studies indicate that low selenium serum concentrations could be related to cardiovascular diseases. Inter alia, risk factors for cardiovascular diseases are physical inactivity, overweight, as well as disadvantageous eating habits. In order to assess whether these risk factors can be modulated, a cardio-protective diet comprising fixed menu plans combined with physical exercise was applied in the German MoKaRi (modulation of cardiovascular risk factors) intervention study. We analyzed serum samples of the MoKaRi cohort (51 participants) for total selenium, GPx activity, and selenoprotein P at different timepoints of the study (0, 10, 20, 40 weeks) to explore the suitability of these selenium-associated markers as indicators of selenium status. Overall, the time-dependent fluctuations in serum selenium concentration suggest a successful change in nutritional and lifestyle behavior. Compared to baseline, a pronounced increase in GPx activity and selenoprotein P was observed, while serum selenium decreased in participants with initially adequate serum selenium content. SELENOP concentration showed a moderate positive monotonic correlation (r = 0.467, p < 0.0001) to total Se concentration, while only a weak linear relationship was observed for GPx activity versus total Se concentration (r = 0.186, p = 0.021). Evidently, other factors apart from the available Se pool must have an impact on the GPx activity, leading to the conclusion that, without having identified these factors, GPx activity should not be used as a status marker for Se}, language = {en} } @misc{SchwarzLossowKoppetal.2019, author = {Schwarz, Maria and Lossow, Kristina and Kopp, Johannes F. and Schwerdtle, Tanja and Kipp, Anna Patricia}, title = {Crosstalk of Nrf2 with the Trace Elements Selenium, Iron, Zinc, and Copper}, series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, number = {1081}, issn = {1866-8372}, doi = {10.25932/publishup-47287}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-472873}, pages = {20}, year = {2019}, abstract = {Trace elements, like Cu, Zn, Fe, or Se, are important for the proper functioning of antioxidant enzymes. However, in excessive amounts, they can also act as pro-oxidants. Accordingly, trace elements influence redox-modulated signaling pathways, such as the Nrf2 pathway. Vice versa, Nrf2 target genes belong to the group of transport and metal binding proteins. In order to investigate whether Nrf2 directly regulates the systemic trace element status, we used mice to study the effect of a constitutive, whole-body Nrf2 knockout on the systemic status of Cu, Zn, Fe, and Se. As the loss of selenoproteins under Se-deprived conditions has been described to further enhance Nrf2 activity, we additionally analyzed the combination of Nrf2 knockout with feeding diets that provide either suboptimal, adequate, or supplemented amounts of Se. Experiments revealed that the Nrf2 knockout partially affected the trace element concentrations of Cu, Zn, Fe, or Se in the intestine, liver, and/or plasma. However, aside from Fe, the other three trace elements were only marginally modulated in an Nrf2-dependent manner. Selenium deficiency mainly resulted in increased plasma Zn levels. One putative mediator could be the metal regulatory transcription factor 1, which was up-regulated with an increasing Se supply and downregulated in Se-supplemented Nrf2 knockout mice.}, 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{ManowskyCamargoKippetal.2016, author = {Manowsky, Julia and Camargo, Rodolfo Gonzalez and Kipp, Anna Patricia and Henkel, Janin and P{\"u}schel, Gerhard Paul}, title = {Insulin-induced cytokine production in macrophages causes insulin resistance in hepatocytes}, series = {American journal of physiology : Endocrinology and metabolism}, volume = {310}, journal = {American journal of physiology : Endocrinology and metabolism}, publisher = {American Chemical Society}, address = {Bethesda}, issn = {0193-1849}, doi = {10.1152/ajpendo.00427.2015}, pages = {E938 -- E946}, year = {2016}, abstract = {Overweight and obesity are associated with hyperinsulinemia, insulin resistance, and a low-grade inflammation. Although hyperinsulinemia is generally thought to result from an attempt of the beta-cell to compensate for insulin resistance, there is evidence that hyperinsulinaemia itself may contribute to the development of insulin resistance and possibly the low-grade inflammation. To test this hypothesis, U937 macrophages were exposed to insulin. In these cells, insulin induced expression of the proinflammatory cytokines IL-1 beta, IL-8, CCL2, and OSM. The insulin-elicited induction of IL-1 beta was independent of the presence of endotoxin and most likely mediated by an insulin-dependent activation of NF-kappa B. Supernatants of the insulin-treated U937 macrophages rendered primary cultures of rat hepatocytes insulin resistant; they attenuated the insulin-dependent induction of glucokinase by 50\%. The cytokines contained in the supernatants of insulin-treated U937 macrophages activated ERK1/2 and IKK beta, resulting in an inhibitory serine phosphorylation of the insulin receptor substrate. In addition, STAT3 was activated and SOCS3 induced, further contributing to the interruption of the insulin receptor signal chain in hepatocytes. These results indicate that hyperinsulinemia per se might contribute to the low-grade inflammation prevailing in overweight and obese patients and thereby promote the development of insulin resistance particularly in the liver, because the insulin concentration in the portal circulation is much higher than in all other tissues.}, language = {en} } @misc{HauffeRathAgyapongetal.2022, author = {Hauffe, Robert and Rath, Michaela and Agyapong, Wilson and Jonas, Wenke and Vogel, Heike and Schulz, Tim Julius and Schwarz, Maria and Kipp, Anna Patricia and Bl{\"u}her, Matthias and Kleinridders, Andr{\´e}}, title = {Obesity Hinders the Protective Effect of Selenite Supplementation on Insulin Signaling}, series = {Zweitver{\"o}ffentlichungen der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, journal = {Zweitver{\"o}ffentlichungen der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, publisher = {Universit{\"a}tsverlag Potsdam}, address = {Potsdam}, issn = {1866-8372}, doi = {10.25932/publishup-56170}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-561709}, pages = {1 -- 16}, year = {2022}, abstract = {The intake of high-fat diets (HFDs) containing large amounts of saturated long-chain fatty acids leads to obesity, oxidative stress, inflammation, and insulin resistance. The trace element selenium, as a crucial part of antioxidative selenoproteins, can protect against the development of diet-induced insulin resistance in white adipose tissue (WAT) by increasing glutathione peroxidase 3 (GPx3) and insulin receptor (IR) expression. Whether selenite (Se) can attenuate insulin resistance in established lipotoxic and obese conditions is unclear. We confirm that GPX3 mRNA expression in adipose tissue correlates with BMI in humans. Cultivating 3T3-L1 pre-adipocytes in palmitate-containing medium followed by Se treatment attenuates insulin resistance with enhanced GPx3 and IR expression and adipocyte differentiation. However, feeding obese mice a selenium-enriched high-fat diet (SRHFD) only resulted in a modest increase in overall selenoprotein gene expression in WAT in mice with unaltered body weight development, glucose tolerance, and insulin resistance. While Se supplementation improved adipocyte morphology, it did not alter WAT insulin sensitivity. However, mice fed a SRHFD exhibited increased insulin content in the pancreas. Overall, while selenite protects against palmitate-induced insulin resistance in vitro, obesity impedes the effect of selenite on insulin action and adipose tissue metabolism in vivo.}, language = {en} } @article{SchwarzLossowKoppetal.2019, author = {Schwarz, Maria and Lossow, Kristina and Kopp, Johannes Florian and Schwerdtle, Tanja and Kipp, Anna Patricia}, title = {Crosstalk of Nrf2 with the Trace Elements Selenium, Iron, Zinc, and Copper}, series = {Nutrients}, volume = {11}, journal = {Nutrients}, number = {9}, publisher = {MDPI}, address = {Basel}, issn = {2072-6643}, doi = {10.3390/nu11092112}, pages = {18}, year = {2019}, abstract = {Trace elements, like Cu, Zn, Fe, or Se, are important for the proper functioning of antioxidant enzymes. However, in excessive amounts, they can also act as pro-oxidants. Accordingly, trace elements influence redox-modulated signaling pathways, such as the Nrf2 pathway. Vice versa, Nrf2 target genes belong to the group of transport and metal binding proteins. In order to investigate whether Nrf2 directly regulates the systemic trace element status, we used mice to study the effect of a constitutive, whole-body Nrf2 knockout on the systemic status of Cu, Zn, Fe, and Se. As the loss of selenoproteins under Se-deprived conditions has been described to further enhance Nrf2 activity, we additionally analyzed the combination of Nrf2 knockout with feeding diets that provide either suboptimal, adequate, or supplemented amounts of Se. Experiments revealed that the Nrf2 knockout partially affected the trace element concentrations of Cu, Zn, Fe, or Se in the intestine, liver, and/or plasma. However, aside from Fe, the other three trace elements were only marginally modulated in an Nrf2-dependent manner. Selenium deficiency mainly resulted in increased plasma Zn levels. One putative mediator could be the metal regulatory transcription factor 1, which was up-regulated with an increasing Se supply and downregulated in Se-supplemented Nrf2 knockout mice.}, 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} }