TY - JOUR A1 - Rohn, Isabelle A1 - Raschke, Stefanie A1 - Aschner, Michael A1 - Tuck, Simon A1 - Kuehnelt, Doris A1 - Kipp, Anna Patricia A1 - Schwerdtle, Tanja A1 - Bornhorst, Julia T1 - Treatment of caenorhabditis elegans with small selenium species enhances antioxidant defense systems JF - Molecular nutrition & food research : bioactivity, chemistry, immunology, microbiology, safety, technology N2 - ScopeSmall selenium (Se) species play a key role in Se metabolism and act as dietary sources of the essential trace element. However, they are redox-active and trigger pro- and antioxidant responses. As health outcomes are strongly species-dependent, species-specific characteristics of Se compounds are tested in vivo. Methods and resultsIn the model organism Caenorhabditis elegans (C. elegans), immediate and sustained effects of selenite, selenomethionine (SeMet), and Se-methylselenocysteine (MeSeCys) are studied regarding their bioavailability, incorporation into proteins, as well as modulation of the cellular redox status. While all tested Se compounds are bioavailable, only SeMet persistently accumulates and is non-specifically incorporated into proteins. However, the protection toward chemically-induced formation of reactive species is independent of the applied Se compound. Increased thioredoxin reductase (TXNRD) activity and changes in mRNA expression levels of antioxidant proteins indicate the activation of cellular defense mechanisms. However, in txnrd-1 deletion mutants, no protective effects of the Se species are observed anymore, which is also reflected by differential gene expression data. ConclusionSe species protect against chemically-induced reactive species formation. The identified immediate and sustained systemic effects of Se species give rise to speculations on possible benefits facing subsequent periods of inadequate Se intake. KW - antioxidant defense systems KW - caenorhabditis elegans KW - selenium KW - oxidative stress KW - selenoproteins Y1 - 2019 U6 - https://doi.org/10.1002/mnfr.201801304 SN - 1613-4125 SN - 1613-4133 VL - 63 IS - 9 PB - Wiley CY - Hoboken ER - TY - JOUR A1 - Nicolai, Merle Marie A1 - Weishaupt, Ann-Kathrin A1 - Baesler, Jessica A1 - Brinkmann, Vanessa A1 - Wellenberg, Anna A1 - Winkelbeiner, Nicola Lisa A1 - Gremme, Anna A1 - Aschner, Michael A1 - Fritz, Gerhard A1 - Schwerdtle, Tanja A1 - Bornhorst, Julia T1 - Effects of manganese on genomic integrity in the multicellular model organism Caenorhabditis elegans JF - International Journal of Molecular Sciences N2 - Although manganese (Mn) is an essential trace element, overexposure is associated with Mn-induced toxicity and neurological dysfunction. Even though Mn-induced oxidative stress is discussed extensively, neither the underlying mechanisms of the potential consequences of Mn-induced oxidative stress on DNA damage and DNA repair, nor the possibly resulting toxicity are characterized yet. In this study, we use the model organism Caenorhabditis elegans to investigate the mode of action of Mn toxicity, focusing on genomic integrity by means of DNA damage and DNA damage response. Experiments were conducted to analyze Mn bioavailability, lethality, and induction of DNA damage. Different deletion mutant strains were then used to investigate the role of base excision repair (BER) and dePARylation (DNA damage response) proteins in Mn-induced toxicity. The results indicate a dose- and time-dependent uptake of Mn, resulting in increased lethality. Excessive exposure to Mn decreases genomic integrity and activates BER. Altogether, this study characterizes the consequences of Mn exposure on genomic integrity and therefore broadens the molecular understanding of pathways underlying Mn-induced toxicity. Additionally, studying the basal poly(ADP-ribosylation) (PARylation) of worms lacking poly(ADP-ribose) glycohydrolase (PARG) parg-1 or parg-2 (two orthologue of PARG), indicates that parg-1 accounts for most of the glycohydrolase activity in worms. KW - manganese KW - oxidative stress KW - DNA repair KW - DNA damage response KW - Caenorhabditis elegans Y1 - 2021 U6 - https://doi.org/10.3390/ijms222010905 SN - 1422-0067 VL - 22 IS - 20 PB - MDPI CY - Basel ER - TY - GEN A1 - Nicolai, Merle Marie A1 - Weishaupt, Ann-Kathrin A1 - Baesler, Jessica A1 - Brinkmann, Vanessa A1 - Wellenberg, Anna A1 - Winkelbeiner, Nicola Lisa A1 - Gremme, Anna A1 - Aschner, Michael A1 - Fritz, Gerhard A1 - Schwerdtle, Tanja A1 - Bornhorst, Julia T1 - Effects of manganese on genomic integrity in the multicellular model organism Caenorhabditis elegans T2 - Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe N2 - Although manganese (Mn) is an essential trace element, overexposure is associated with Mn-induced toxicity and neurological dysfunction. Even though Mn-induced oxidative stress is discussed extensively, neither the underlying mechanisms of the potential consequences of Mn-induced oxidative stress on DNA damage and DNA repair, nor the possibly resulting toxicity are characterized yet. In this study, we use the model organism Caenorhabditis elegans to investigate the mode of action of Mn toxicity, focusing on genomic integrity by means of DNA damage and DNA damage response. Experiments were conducted to analyze Mn bioavailability, lethality, and induction of DNA damage. Different deletion mutant strains were then used to investigate the role of base excision repair (BER) and dePARylation (DNA damage response) proteins in Mn-induced toxicity. The results indicate a dose- and time-dependent uptake of Mn, resulting in increased lethality. Excessive exposure to Mn decreases genomic integrity and activates BER. Altogether, this study characterizes the consequences of Mn exposure on genomic integrity and therefore broadens the molecular understanding of pathways underlying Mn-induced toxicity. Additionally, studying the basal poly(ADP-ribosylation) (PARylation) of worms lacking poly(ADP-ribose) glycohydrolase (PARG) parg-1 or parg-2 (two orthologue of PARG), indicates that parg-1 accounts for most of the glycohydrolase activity in worms. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 1173 KW - manganese KW - oxidative stress KW - DNA repair KW - DNA damage response KW - Caenorhabditis elegans Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-523275 SN - 1866-8372 IS - 1173 ER - TY - JOUR A1 - Ijomone, Omamuyovwi M. A1 - Iroegbu, Joy D. A1 - Morcillo, Patricia A1 - Ayodele, Akinyemi J. A1 - Ijomone, Olayemi K. A1 - Bornhorst, Julia A1 - Schwerdtle, Tanja A1 - Aschner, Michael T1 - Sex-dependent metal accumulation and immunoexpression of Hsp70 and Nrf2 in rats' brain following manganese exposure JF - Environmental toxicology N2 - Manganese (Mn), although important for multiple cellular processes, has posed environmental health concerns due to its neurotoxic effects. In recent years, there have been extensive studies on the mechanism of Mn-induced neuropathology, as well as the sex-dependent vulnerability to its neurotoxic effects. Nonetheless, cellular mechanisms influenced by sex differences in susceptibility to Mn have yet to be adequately characterized. Since oxidative stress is a key mechanism of Mn neurotoxicity, here, we have probed Hsp70 and Nrf2 proteins to investigate the sex-dependent changes following exposure to Mn. Male and female rats were administered intraperitoneal injections of MnCl2 (10 mg/kg and 25 mg/kg) 48 hourly for a total of eight injections (15 days). We evaluated changes in body weight, as well as Mn accumulation, Nrf2 and Hsp70 expression across four brain regions; striatum, cortex, hippocampus and cerebellum in both sexes. Our results showed sex-specific changes in body-weight, specifically in males but not in females. Additionally, we noted sex-dependent accumulation of Mn in the brain, as well as in expression levels of Nrf2 and Hsp70 proteins. These findings revealed sex-dependent susceptibility to Mn-induced neurotoxicity corresponding to differential Mn accumulation, and expression of Hsp70 and Nrf2 across several brain regions. KW - brain KW - female KW - male KW - manganese KW - oxidative stress Y1 - 2022 U6 - https://doi.org/10.1002/tox.23583 SN - 1520-4081 SN - 1522-7278 VL - 37 IS - 9 SP - 2167 EP - 2177 PB - Wiley CY - New York, NY ER -