@article{KorovilaHoehnJungetal.2021, author = {Korovila, Ioanna and Hoehn, Annika and Jung, Tobias and Grune, Tilman and Ott, Christiane}, title = {Reduced liver autophagy in high-fat diet induced liver steatosis in New Zealand obese mice}, series = {Antioxidants : open access journal}, volume = {10}, journal = {Antioxidants : open access journal}, number = {4}, publisher = {MDPI}, address = {Basel}, issn = {2076-3921}, doi = {10.3390/antiox10040501}, pages = {10}, year = {2021}, abstract = {Non-alcoholic fatty liver disease (NAFLD), as a consequence of overnutrition caused by high-calorie diets, results in obesity and disturbed lipid homeostasis leading to hepatic lipid droplet formation. Lipid droplets can impair hepatocellular function; therefore, it is of utmost importance to degrade these cellular structures. This requires the normal function of the autophagic-lysosomal system and the ubiquitin-proteasomal system. We demonstrated in NZO mice, a polygenic model of obesity, which were compared to C57BL/6J (B6) mice, that a high-fat diet leads to obesity and accumulation of lipid droplets in the liver. This was accompanied by a loss of autophagy efficiency whereas the activity of lysosomal proteases and the 20S proteasome remained unaffected. The disturbance of cellular protein homeostasis was further demonstrated by the accumulation of 3-nitrotyrosine and 4-hydroxynonenal modified proteins, which are normally prone to degradation. Therefore, we conclude that fat accumulation in the liver due to a high-fat diet is associated with a failure of autophagy and leads to the disturbance of proteostasis. This might further contribute to lipid droplet stabilization and accumulation.}, language = {en} } @article{GilCoullJonasetal.2022, author = {Gil, Carla Igual and Coull, Bethany M. and Jonas, Wenke and Lippert, Rachel N. and Klaus, Susanne and Ost, Mario}, title = {Mitochondrial stress-induced GFRAL signaling controls diurnal food intake and anxiety-like behavior}, series = {Life Science Alliance}, volume = {5}, journal = {Life Science Alliance}, number = {11}, publisher = {EMBO Press}, address = {Heidelberg}, issn = {2575-1077}, doi = {10.26508/lsa.202201495}, pages = {11}, year = {2022}, abstract = {Growth differentiation factor 15 (GDF15) is a mitochondrial stressinduced cytokine that modulates energy balance in an endocrine manner. However, the importance of its brainstem-restricted receptor GDNF family receptor alpha-like (GFRAL) to mediate endocrine GDF15 signaling to the brain uponmitochondrial dysfunction is still unknown. Using a mouse model with muscle-specific mitochondrial dysfunction, we here show that GFRAL is required for activation of systemic energy metabolism via daytime-restricted anorexia but not responsible for muscle wasting. We further find that muscle mitochondrial stress response involves a GFRAL-dependent induction of hypothalamic corticotropin-releasing hormone, without elevated corticosterone levels. Finally, we identify that GFRAL signaling governs an anxiety-like behavior in male mice with muscle mitochondrial dysfunction, with females showing a less robust GFRAL-dependent anxiety-like phenotype. Together, we here provide novel evidence of a mitochondrial stress-induced muscle-brain crosstalk via the GDF15-GFRAL axis to modulate food intake and anxiogenic behavior.}, language = {en} } @article{WittekToumaNitezkietal.2023, author = {Wittek, Laura and Touma, Chadi and Nitezki, Tina and Laeger, Thomas and Kr{\"a}mer, Stephanie and Raila, Jens}, title = {Reduction in cold stress in an innovative metabolic cage housing system increases animal welfare in laboratory mice}, series = {Animals}, volume = {13}, journal = {Animals}, number = {18}, publisher = {MDPI}, address = {Basel}, issn = {2076-2615}, doi = {10.3390/ani13182866}, pages = {21}, year = {2023}, abstract = {Housing in metabolic cages can induce a pronounced stress response. Metabolic cage systems imply housing mice on metal wire mesh for the collection of urine and feces in addition to monitoring food and water intake. Moreover, mice are single-housed, and no nesting, bedding, or enrichment material is provided, which is often argued to have a not negligible impact on animal welfare due to cold stress. We therefore attempted to reduce stress during metabolic cage housing for mice by comparing an innovative metabolic cage (IMC) with a commercially available metabolic cage from Tecniplast GmbH (TMC) and a control cage. Substantial refinement measures were incorporated into the IMC cage design. In the frame of a multifactorial approach for severity assessment, parameters such as body weight, body composition, food intake, cage and body surface temperature (thermal imaging), mRNA expression of uncoupling protein 1 (Ucp1) in brown adipose tissue (BAT), fur score, and fecal corticosterone metabolites (CMs) were included. Female and male C57BL/6J mice were single-housed for 24 h in either conventional Macrolon cages (control), IMC, or TMC for two sessions. Body weight decreased less in the IMC (females—1st restraint: -6.94\%; 2nd restraint: -6.89\%; males—1st restraint: -8.08\%; 2nd restraint: -5.82\%) compared to the TMC (females—1st restraint: -13.2\%; 2nd restraint: -15.0\%; males—1st restraint: -13.1\%; 2nd restraint: -14.9\%) and the IMC possessed a higher cage temperature (females—1st restraint: 23.7 °C; 2nd restraint: 23.5 °C; males—1st restraint: 23.3 °C; 2nd restraint: 23.5 °C) compared with the TMC (females—1st restraint: 22.4 °C; 2nd restraint: 22.5 °C; males—1st restraint: 22.6 °C; 2nd restraint: 22.4 °C). The concentration of fecal corticosterone metabolites in the TMC (females—1st restraint: 1376 ng/g dry weight (DW); 2nd restraint: 2098 ng/g DW; males—1st restraint: 1030 ng/g DW; 2nd restraint: 1163 ng/g DW) was higher compared to control cage housing (females—1st restraint: 640 ng/g DW; 2nd restraint: 941 ng/g DW; males—1st restraint: 504 ng/g DW; 2nd restraint: 537 ng/g DW). Our results show the stress potential induced by metabolic cage restraint that is markedly influenced by the lower housing temperature. The IMC represents a first attempt to target cold stress reduction during metabolic cage application thereby producing more animal welfare friendlydata.}, language = {en} } @article{RadbruchPischonDuetal.2022, author = {Radbruch, Moritz Jan Florian and Pischon, Jeanette Hannah Charlotte and Du, Fang and Haag, Rainer and Schumacher, Fabian and Kleuser, Burkhard and Mundhenk, Lars and Gruber, Achim}, title = {Biodegradable core-multishell nanocarrier: topical tacrolimus delivery for treatment of dermatitis}, series = {Journal of controlled release : official journal of the Controlled Release Society and of the Japanese Society of Drug Delivery Systems}, volume = {349}, journal = {Journal of controlled release : official journal of the Controlled Release Society and of the Japanese Society of Drug Delivery Systems}, publisher = {Elsevier}, address = {New York, NY [u.a.]}, issn = {0168-3659}, doi = {10.1016/j.jconrel.2022.07.025}, pages = {917 -- 928}, year = {2022}, abstract = {Two challenges in topical drug delivery to the skin include solubilizing hydrophobic drugs in water-based formulations and increasing drug penetration into the skin. Polymeric core-multishell nanocarrier (CMS), particularly the novel biodegradable CMS (bCMS = hPG-PCL1.1K-mPEG(2k)-CMS) have shown both advantages on excised skin ex vivo. Here, we investigated topical delivery of tacrolimus (TAC; > 500 g/mol) by bCMS in a hydrogel on an oxazolone-induced model of dermatitis in vivo. As expected, bCMS successfully delivered TAC into the skin. However, in vivo they did not increase, but decrease TAC penetration through the stratum corneum compared to ointment. Differences in the resulting mean concentrations were mostly non-significant in the skin (epidermis: 35.7 +/- 20.9 ng/cm(2) for bCMS vs. 92.6 +/- 62.7 ng/cm(2) for ointment; dermis: 76.8 +/- 26.8 ng/cm(2) vs 118.2 +/- 50.4 ng/cm(2)), but highly significant in blood (plasma: 1.1 +/- 0.4 ng/ml vs 11.3 +/- 9.3 ng/ml; erythrocytes: 0.5 +/- 0.2 ng/ml vs 3.4 +/- 2.4 ng/ml) and liver (0.01 +/- 0.01 ng/mg vs 0.03 +/- 0.01 ng/mg). bCMS were detected in the stratum corneum but not in viable skin or beyond. The therapeutic efficacy of TAC delivered by bCMS was equivalent to that of standard TAC ointment. Our results suggest that bCMS may be a promising carrier for the topical delivery of TAC. The quantitative difference to previous results should be interpreted in light of structural differences between murine and human skin, but highlights the need as well as potential methods to develop more a complex ex vivo analysis on human skin to ensure quantitative predictive value.}, language = {en} } @article{JonasSchwerbelZellneretal.2022, author = {Jonas, Wenke and Schwerbel, Kristin and Zellner, Lisa and J{\"a}hnert, Markus and Gottmann, Pascal and Sch{\"u}rmann, Annette}, title = {Alterations of lipid profile in livers with impaired lipophagy}, series = {International journal of molecular sciences}, volume = {23}, journal = {International journal of molecular sciences}, number = {19}, publisher = {MDPI}, address = {Basel}, issn = {1422-0067}, doi = {10.3390/ijms231911863}, pages = {12}, year = {2022}, abstract = {Non-alcoholic fatty liver disease (NAFLD) is characterized by excessive lipid accumulation in the liver. Various mechanisms such as an increased uptake in fatty acids or de novo synthesis contribute to the development of steatosis and progression to more severe stages. Furthermore, it has been shown that impaired lipophagy, the degradation of lipids by autophagic processes, contributes to NAFLD. Through an unbiased lipidome analysis of mouse livers in a genetic model of impaired lipophagy, we aimed to determine the resulting alterations in the lipidome. Observed changes overlap with those of the human disease. Overall, the entire lipid content and in particular the triacylglycerol concentration increased under conditions of impaired lipophagy. In addition, we detected a reduction in long-chain polyunsaturated fatty acids (PUFAs) and an increased ratio of n-6 PUFAs to n-3 PUFAs, which was due to the depletion of n-3 PUFAs. Although the abundance of major phospholipid classes was reduced, the ratio of phosphatidylcholines to phosphatidylethanolamines was not affected. In conclusion, this study demonstrates that impaired lipophagy contributes to the pathology of NAFLD and is associated with an altered lipid profile. However, the lipid pattern does not appear to be specific for lipophagic alterations, as it resembles mainly that described in relation to fatty liver disease.}, language = {en} } @article{HuschekRawelSchweikertetal.2022, author = {Huschek, Gerd and Rawel, Harshadrai M. and Schweikert, Torsten and Henkel-Oberl{\"a}nder, Janin and Sagu Tchewonpi, Sorel}, title = {Characterization and optimization of microwave-assisted extraction of B-phycoerythrin from Porphyridium purpureum using response surface methodology and Doehlert design}, series = {Bioresource Technology Reports}, volume = {19}, journal = {Bioresource Technology Reports}, publisher = {Elsevier}, address = {Amsterdam}, issn = {2589-014X}, doi = {10.1016/j.biteb.2022.101212}, pages = {9}, year = {2022}, abstract = {Microalgae are one of the most promising food source of the future. Nowadays, extracts of high-value active substances of biomass are business aims for the development of food additives in personalized nutrition, in cosmetics and pharmaceuticals. A new-patented vertical farming cultivation technology was used for production of Porphyridium purpureum. In this work, microwave assisted extraction was used to extract B-phycoerythrin from Porphyridium purpureum biomass. Response surface methodology was implemented for optimization. Numerical optimization established the best point of the experimental domain (biomass/solvent of 16.8 mg/mL, time of 172 s, and temperature of 30 degrees C) with a desirability value of 0.82. Corresponding experimental responses values of 7.2 mg, 8.5 \% and 13,961 PA/mu g biomass were obtained for extracted proteins, extraction yield and extracted B-phycoerythrin, respectively. Final freeze-dried product indicated protein content of 55 \% using Kjeldahl while targeted mass spectrometry analysis revealed that B-phycoerythrin represented 93 \% of the total protein.}, language = {en} } @article{RuszkiewiczPapatheodorouJaecketal.2023, author = {Ruszkiewicz, Joanna and Papatheodorou, Ylea and J{\"a}ck, Nathalie and Melzig, Jasmin and Eble, Franziska and Pirker, Annika and Thomann, Marius and Haberer, Andreas and Rothmiller, Simone and B{\"u}rkle, Alexander and Mangerich, Aswin}, title = {NAD+ Acts as a protective factor in cellular stress response to DNA alkylating agents}, series = {Cells : open access journal}, volume = {12}, journal = {Cells : open access journal}, number = {19}, publisher = {MDPI}, address = {Basel}, issn = {2073-4409}, doi = {10.3390/cells12192396}, pages = {22}, year = {2023}, abstract = {Sulfur mustard (SM) and its derivatives are potent genotoxic agents, which have been shown to trigger the activation of poly (ADP-ribose) polymerases (PARPs) and the depletion of their substrate, nicotinamide adenine dinucleotide (NAD+). NAD+ is an essential molecule involved in numerous cellular pathways, including genome integrity and DNA repair, and thus, NAD+ supplementation might be beneficial for mitigating mustard-induced (geno)toxicity. In this study, the role of NAD+ depletion and elevation in the genotoxic stress response to SM derivatives, i.e., the monofunctional agent 2-chloroethyl-ethyl sulfide (CEES) and the crosslinking agent mechlorethamine (HN2), was investigated with the use of NAD+ booster nicotinamide riboside (NR) and NAD+ synthesis inhibitor FK866. The effects were analyzed in immortalized human keratinocytes (HaCaT) or monocyte-like cell line THP-1. In HaCaT cells, NR supplementation, increased NAD+ levels, and elevated PAR response, however, did not affect ATP levels or DNA damage repair, nor did it attenuate long- and short-term cytotoxicities. On the other hand, the depletion of cellular NAD+ via FK866 sensitized HaCaT cells to genotoxic stress, particularly CEES exposure, whereas NR supplementation, by increasing cellular NAD+ levels, rescued the sensitizing FK866 effect. Intriguingly, in THP-1 cells, the NR-induced elevation of cellular NAD+ levels did attenuate toxicity of the mustard compounds, especially upon CEES exposure. Together, our results reveal that NAD+ is an important molecule in the pathomechanism of SM derivatives, exhibiting compound-specificity. Moreover, the cell line-dependent protective effects of NR are indicative of system-specificity of the application of this NAD+ booster.}, language = {en} } @article{SaguTchewonpiRawelRohn2022, author = {Sagu Tchewonpi, Sorel and Rawel, Harshadrai M. and Rohn, Sascha}, title = {Targeted bottom-up mass spectrometry approach for the relative quantification of post-translational modification of bovine κ-casein during milk fermentation}, series = {Molecules}, volume = {27}, journal = {Molecules}, number = {18}, publisher = {MDPI}, address = {Basel}, issn = {1420-3049}, doi = {10.3390/molecules27185834}, pages = {17}, year = {2022}, abstract = {kappa-casein (kappa-CN) is one of the key components in bovine milk, playing a unique role in the structuration of casein micelles. It contains in its chemical structure up to sixteen amino acid residues (mainly serine and threonine) susceptible to modifications, including glycosylation and phosphorylation, which may further be formed during milk processing. In this study, changes in post-translational modification (PTM) of kappa-CN during bovine milk fermentation were investigated. One-to-five-day fermented milk samples were produced. A traditional bottom-up proteomics approach was used to establish a multiple-reaction monitoring (MRM) method for relative quantification of kappa-CN PTM. Endoproteinase Glu-C was found to efficiently digest the kappa-CN molecule. The developed LC-MS method was validated by performing assessments of linearity, precision, repeatability, reproducibility, limit of detection (LOD), and limit of quantification (LOQ). Among the yielded peptides, four of them containing serine and threonine residues were identified and the unmodified as well as the modified variants of each of them were relatively quantified. These peptides were (1) IPTINTIASGEPTSTTE ([140, 158]), (2) STVATLE ([162, 168]), (3) DSPE ([169, 172]), and (4) INTVQVTSTAV ([180, 190]). Distribution analysis between unmodified and modified peptides revealed that over 50\% of kappa-CN was found in one of its modified forms in milk. The fermentation process further significantly altered the composition between unmodified/modified kappa-CN, with glycoslaytion being predominant compared to phosphorylation (p < 0.01). Further method development towards alpha and beta-CN fractions and their PTM behavior would be an asset to better understand the changes undergone by milk proteins and the micellar structure during fermentation.}, language = {en} } @inproceedings{SchulzeDoeschnerGoegeretal.2022, author = {Schulze, Kora and D{\"o}schner, Larissa and G{\"o}ger, Lea and Franz, K. and M{\"u}ller-Werdan, Ursula and Norman, Kristina and Herpich, Catrin}, title = {Kurzeitige vegane Intervention senkt Inflammationsmarker}, series = {Zeitschrift f{\"u}r Gerontologie und Geriatrie : Organ der Deutschen Gesellschaft f{\"u}r Gerontologie und Geriatrie}, volume = {55}, booktitle = {Zeitschrift f{\"u}r Gerontologie und Geriatrie : Organ der Deutschen Gesellschaft f{\"u}r Gerontologie und Geriatrie}, number = {Supplement 1}, publisher = {Springer Medizin}, address = {Heidelberg}, issn = {0948-6704}, doi = {10.1007/s00391-022-02095-7}, pages = {S83 -- S84}, year = {2022}, language = {de} } @phdthesis{Friese2024, author = {Friese, Sharleen}, title = {Trace elements and genomic instability in the murine brain}, school = {Universit{\"a}t Potsdam}, pages = {XV, 112, XXI}, year = {2024}, abstract = {The trace elements copper, iron, manganese, selenium and zinc are essential micronutrients involved in various cellular processes, all with different responsibilities. Based on that importance, their concentrations are tightly regulated in mammalian organisms. The maintenance of those levels is termed trace element homeostasis and mediated by a combination of processes regulating absorption, cellular and systemic transport mechanisms, storage and effector proteins as well as excretion. Due to their chemical properties, some functions of trace elements overlap, as seen in antioxidative defence, for example, comprising an expansive spectrum of antioxidative proteins and molecules. Simultaneously, the same is true for regulatory mechanisms, causing trace elements to influence each other's homeostases. To mimic physiological conditions, trace elements should therefore not be evaluated separately but considered in parallel. While many of these homeostatic mechanisms are well-studied, for some elements new pathways are still discovered. Additionally, the connections between dietary trace element intake, trace element status and health are not fully unraveled, yet. With current demographic developments, also the influence of ageing as well as of certain pathological conditions is of increasing interest. Here, the TraceAge research unit was initiated, aiming to elucidate the homeostases of and interactions between essential trace elements in healthy and diseased elderly. While human cohort studies can offer insights into trace element profiles, also in vivo model organisms are used to identify underlying molecular mechanisms. This is achieved by a set of feeding studies including mice of various age groups receiving diets of reduced trace element content. To account for cognitive deterioration observed with ageing, neurodegenerative diseases, as well as genetic mutations triggering imbalances in cerebral trace element concentrations, one TraceAge work package focuses on trace elements in the murine brain, specifically the cerebellum. In that context, concentrations of the five essential trace elements of interest, copper, iron, manganese, selenium and zinc, were quantified via inductively coupled plasma-tandem mass spectrometry, revealing differences in priority of trace element homeostases between brain and liver. Upon moderate reduction of dietary trace element supply, cerebellar concentrations of copper and manganese deviated from those in adequately supplied animals. By further reduction of dietary trace element contents, also concentrations of cerebellar iron and selenium were affected, but not as strong as observed in liver tissue. In contrast, zinc concentrations remained stable. Investigation of aged mice revealed cerebellar accumulation of copper and iron, possibly contributing to oxidative stress on account of their redox properties. Oxidative stress affects a multitude of cellular components and processes, among them, next to proteins and lipids, also the DNA. Direct insults impairing its integrity are of relevance here, but also indirect effects, mediated by the machinery ensuring genomic stability and its functionality. The system includes the DNA damage response, comprising detection of endogenous and exogenous DNA lesions, decision on subsequent cell fate and enabling DNA repair, which presents another pillar of genomic stability maintenance. Also in proteins of this machinery, trace elements act as cofactors, shaping the hypothesis of impaired genomic stability maintenance under conditions of disturbed trace element homeostasis. To investigate this hypothesis, a variety of approaches was used, applying OECD guidelines Organisation for Economic Co-operation and Development, adapting existing protocols for use in cerebellum tissue and establishing new methods. In order to assess the impact of age and dietary trace element depletion on selected endpoints estimating genomic instability, DNA damage and DNA repair were investigated. DNA damage analysis, in particular of DNA strand breaks and oxidatively modified DNA bases, revealed stable physiological levels which were neither affected by age nor trace element supply. To examine whether this is a result of increased repair rates, two steps characteristic for base excision repair, namely DNA incision and ligation activity, were studied. DNA glycosylases and DNA ligases were not reduced in their activity by age or trace element depletion, either. Also on the level of gene expression, major proteins involved in genomic stability maintenance were analysed, mirroring results obtained from protein studies. To conclude, the present work describes homeostatic regulation of trace elements in the brain, which, in absence of genetic mutations, is able to retain physiological levels even under conditions of reduced trace element supply to a certain extent. This is reflected by functionality of genomic stability maintenance mechanisms, illuminating the prioritization of the brain as vital organ.}, language = {en} } @article{SchellKleinridders2022, author = {Schell, Mareike and Kleinridders, Andr{\´e}}, title = {Intuitives Essen? Zentrale Regulation der Nahrungsaufnahme durch N{\"a}hrstoffe und Stoffwechselhormone}, series = {Ern{\"a}hrungsumschau}, volume = {69}, journal = {Ern{\"a}hrungsumschau}, number = {11}, publisher = {Umschau-Zeitschriftenverlag}, address = {Frankfurt, M.}, issn = {0174-0008}, pages = {M610 -- M620}, year = {2022}, subject = {Adipositas}, language = {de} } @misc{KleinriddersMaidKohnert2022, author = {Kleinridders, Andre and Maid-Kohnert, Udo}, title = {"Intuitives Essen ist f{\"u}r adip{\"o}se Patienten nur schwer umzusetzen!"}, series = {Ern{\"a}hrungsumschau}, volume = {69}, journal = {Ern{\"a}hrungsumschau}, number = {11}, publisher = {Umschau-Zeitschriftenverlag}, address = {Frankfurt am Main}, issn = {0174-0008}, pages = {M622 -- M625}, year = {2022}, language = {de} } @article{PuchkovMuellerLehmannetal.2023, author = {Puchkov, Dmytro and M{\"u}ller, Paul Markus and Lehmann, Martin and Matth{\"a}us, Claudia}, title = {Analyzing the cellular plasma membrane by fast and efficient correlative STED and platinum replica EM}, series = {Frontiers in cell and developmental biology}, volume = {11}, journal = {Frontiers in cell and developmental biology}, publisher = {Frontiers Media}, address = {Lausanne}, issn = {2296-634X}, doi = {10.3389/fcell.2023.1305680}, pages = {15}, year = {2023}, abstract = {The plasma membrane of mammalian cells links transmembrane receptors, various structural components, and membrane-binding proteins to subcellular processes, allowing inter- and intracellular communication. Therefore, membrane-binding proteins, together with structural components such as actin filaments, modulate the cell membrane in their flexibility, stiffness, and curvature. Investigating membrane components and curvature in cells remains challenging due to the diffraction limit in light microscopy. Preparation of 5-15-nm-thin plasma membrane sheets and subsequent inspection by metal replica transmission electron microscopy (TEM) reveal detailed information about the cellular membrane topology, including the structure and curvature. However, electron microscopy cannot identify proteins associated with specific plasma membrane domains. Here, we describe a novel adaptation of correlative super-resolution light microscopy and platinum replica TEM (CLEM-PREM), allowing the analysis of plasma membrane sheets with respect to their structural details, curvature, and associated protein composition. We suggest a number of shortcuts and troubleshooting solutions to contemporary PREM protocols. Thus, implementation of super-resolution stimulated emission depletion (STED) microscopy offers significant reduction in sample preparation time and reduced technical challenges for imaging and analysis. Additionally, highly technical challenges associated with replica preparation and transfer on a TEM grid can be overcome by scanning electron microscopy (SEM) imaging. The combination of STED microscopy and platinum replica SEM or TEM provides the highest spatial resolution of plasma membrane proteins and their underlying membrane and is, therefore, a suitable method to study cellular events like endocytosis, membrane trafficking, or membrane tension adaptations.}, language = {en} } @article{RuszkiewiczEndigGueveretal.2023, author = {Ruszkiewicz, Joanna and Endig, Lisa and G{\"u}ver, Ebru and B{\"u}rkle, Alexander and Mangerich, Aswin}, title = {Life-cycle-dependent toxicities of mono- and bifunctional alkylating agents in the 3R-compliant model organism C. elegans}, series = {Cells : open access journal}, volume = {12}, journal = {Cells : open access journal}, number = {23}, publisher = {MDPI}, address = {Basel}, issn = {2073-4409}, doi = {10.3390/cells12232728}, pages = {16}, year = {2023}, abstract = {Caenorhabditis elegans (C. elegans) is gaining recognition and importance as an organismic model for toxicity testing in line with the 3Rs principle (replace, reduce, refine). In this study, we explored the use of C. elegans to examine the toxicities of alkylating sulphur mustard analogues, specifically the monofunctional agent 2-chloroethyl-ethyl sulphide (CEES) and the bifunctional, crosslinking agent mechlorethamine (HN2). We exposed wild-type worms at different life cycle stages (from larvae L1 to adulthood day 10) to CEES or HN2 and scored their viability 24 h later. The susceptibility of C. elegans to CEES and HN2 paralleled that of human cells, with HN2 exhibiting higher toxicity than CEES, reflected in LC50 values in the high µM to low mM range. Importantly, the effects were dependent on the worms' developmental stage as well as organismic age: the highest susceptibility was observed in L1, whereas the lowest was observed in L4 worms. In adult worms, susceptibility to alkylating agents increased with advanced age, especially to HN2. To examine reproductive effects, L4 worms were exposed to CEES and HN2, and both the offspring and the percentage of unhatched eggs were assessed. Moreover, germline apoptosis was assessed by using ced-1p::GFP (MD701) worms. In contrast to concentrations that elicited low toxicities to L4 worms, CEES and HN2 were highly toxic to germline cells, manifesting as increased germline apoptosis as well as reduced offspring number and percentage of eggs hatched. Again, HN2 exhibited stronger effects than CEES. Compound specificity was also evident in toxicities to dopaminergic neurons-HN2 exposure affected expression of dopamine transporter DAT-1 (strain BY200) at lower concentrations than CEES, suggesting a higher neurotoxic effect. Mechanistically, nicotinamide adenine dinucleotide (NAD+) has been linked to mustard agent toxicities. Therefore, the NAD+-dependent system was investigated in the response to CEES and HN2 treatment. Overall NAD+ levels in worm extracts were revealed to be largely resistant to mustard exposure except for high concentrations, which lowered the NAD+ levels in L4 worms 24 h post-treatment. Interestingly, however, mutant worms lacking components of NAD+-dependent pathways involved in genome maintenance, namely pme-2, parg-2, and sirt-2.1 showed a higher and compound-specific susceptibility, indicating an active role of NAD+ in genotoxic stress response. In conclusion, the present results demonstrate that C. elegans represents an attractive model to study the toxicology of alkylating agents, which supports its use in mechanistic as well as intervention studies with major strength in the possibility to analyze toxicities at different life cycle stages.}, language = {en} } @article{SchellWardelmannHauffeetal.2023, author = {Schell, Mareike and Wardelmann, Kristina and Hauffe, Robert and Rath, Michaela and Chopra, Simran and Kleinridders, Andr{\´e}}, title = {Lactobacillus rhamnosus sex-specifically attenuates depressive-like behavior and mitigates metabolic consequences in obesity}, series = {Biological psychiatry: global open science}, volume = {3}, journal = {Biological psychiatry: global open science}, number = {4}, publisher = {Elsevier}, address = {Amsterdam}, issn = {2667-1743}, doi = {10.1016/j.bpsgos.2023.02.011}, pages = {651 -- 662}, year = {2023}, abstract = {BACKGROUND: Patients with diabetes exhibit an increased prevalence for emotional disorders compared with healthy humans, partially due to a shared pathogenesis including hormone resistance and inflammation, which is also linked to intestinal dysbiosis. The preventive intake of probiotic lactobacilli has been shown to improve dysbiosis along with mood and metabolism. Yet, a potential role of Lactobacillus rhamnosus (Lacticaseibacillus rhamnosus 0030) (LR) in improving emotional behavior in established obesity and the underlying mechanisms are unknown. METHODS: Female and male C57BL/6N mice were fed a low-fat diet (10\% kcal from fat) or high-fat diet (HFD) (45\% kcal from fat) for 6 weeks, followed by daily oral gavage of vehicle or 1 3 10 8 colony-forming units of LR, and assessment of anxiety- and depressive-like behavior. Cecal microbiota composition was analyzed using 16S ribosomal RNA sequencing, plasma and cerebrospinal fluid were collected for metabolomic analysis, and gene expression of different brain areas was assessed using reverse transcriptase quantitative polymerase chain reaction. RESULTS: We observed that 12 weeks of HFD feeding induced hyperinsulinemia, which was attenuated by LR application only in female mice. On the contrary, HFD-fed male mice exhibited increased anxiety- and depressive-like behavior, where the latter was specifically attenuated by LR application, which was independent of metabolic changes. Furthermore, LR application restored the HFD-induced decrease of tyrosine hydroxylase, along with normalizing cholecystokinin gene expression in dopaminergic brain regions; both tyrosine hydroxylase and cholecystokinin are involved in signaling pathways impacting emotional disorders. CONCLUSIONS: Our data show that LR attenuates depressive-like behavior after established obesity, with changes in the dopaminergic system in male mice, and mitigates hyperinsulinemia in obese female mice.}, language = {en} } @article{KrokeSchmidtAminietal.2022, author = {Kroke, Anja and Schmidt, Annemarie and Amini, Anna M. and Kalotai, Nicole and Lehmann, Andreas and Haardt, Julia and Bauer, J{\"u}rgen M. and Bischoff-Ferrari, Heike A. and Boeing, Heiner and Egert, Sarah and Ellinger, Sabine and K{\"u}hn, Tilman and Louis, Sandrine and Lorkowski, Stefan and Nimptsch, Katharina and Remer, Thomas and Schulze, Matthias B. and Siener, Roswitha and Stangl, Gabriele and Volkert, Dorothee and Zittermann, Armin and Buyken, Anette E. and Watzl, Bernhard and Schwingshackl, Lukas}, title = {Dietary protein intake and health-related outcomes: a methodological protocol for the evidence evaluation and the outline of an evidence to decision framework underlying the evidence-based guideline of the German Nutrition Society}, series = {European journal of nutrition}, volume = {61}, journal = {European journal of nutrition}, number = {4}, publisher = {Springer Nature}, address = {Heidelberg}, organization = {German Nutr Soc}, issn = {1436-6207}, doi = {10.1007/s00394-021-02789-5}, pages = {2091 -- 2101}, year = {2022}, abstract = {Purpose: The present work aimed to delineate (i) a revised protocol according to recent methodological developments in evidence generation, to (ii) describe its interpretation, the assessment of the overall certainty of evidence and to (iii) outline an Evidence to Decision framework for deriving an evidence-based guideline on quantitative and qualitative aspects of dietary protein intake. Methods A methodological protocol to systematically investigate the association between dietary protein intake and several health outcomes and for deriving dietary protein intake recommendations for the primary prevention of various non-communicable diseases in the general adult population was developed. Results The developed methodological protocol relies on umbrella reviews including systematic reviews with or without meta-analyses. Systematic literature searches in three databases will be performed for each health-related outcome. The methodological quality of all selected systematic reviews will be evaluated using a modified version of AMSTAR 2, and the outcome-specific certainty of evidence for systematic reviews with or without meta-analysis will be assessed with NutriGrade. The general outline of the Evidence to Decision framework foresees that recommendations in the derived guideline will be given based on the overall certainty of evidence as well as on additional criteria such as sustainability. Conclusion The methodological protocol permits a systematic evaluation of published systematic reviews on dietary protein intake and its association with selected health-related outcomes. An Evidence to Decision framework will be the basis for the overall conclusions and the resulting recommendations for dietary protein intake.}, language = {en} } @article{LiSchlaichZhangetal.2021, author = {Li, Mingjun and Schlaich, Christoph and Zhang, Jianguang and Donskyi, Ievgen and Schwibbert, Karin and Schreiber, Frank and Xia, Yi and Radnik, J{\"o}rg and Schwerdtle, Tanja and Haag, Rainer}, title = {Mussel-inspired multifunctional coating for bacterial infection prevention and osteogenic induction}, series = {Journal of materials science \& technology : JMST ; an international journal / spons. by the Chinese Society for Metals (CSM), the Chinese Materials Research Society (CMRS), Institute of Metal Research, Chinese Academy of Sciences}, volume = {68}, journal = {Journal of materials science \& technology : JMST ; an international journal / spons. by the Chinese Society for Metals (CSM), the Chinese Materials Research Society (CMRS), Institute of Metal Research, Chinese Academy of Sciences}, publisher = {Elsevier}, address = {Amsterdam [u.a.]}, issn = {1005-0302}, doi = {10.1016/j.jmst.2020.08.011}, pages = {160 -- 171}, year = {2021}, abstract = {Bacterial infection and osteogenic integration are the two main problems that cause severe complications after surgeries. In this study, the antibacterial and osteogenic properties were simultaneously introduced in biomaterials, where copper nanoparticles (CuNPs) were generated by in situ reductions of Cu ions into a mussel-inspired hyperbranched polyglycerol (MI-hPG) coating via a simple dip-coating method. This hyperbranched polyglycerol with 10 \% catechol groups' modification presents excellent antifouling property, which could effectively reduce bacteria adhesion on the surface. In this work, polycaprolactone (PCL) electrospun fiber membrane was selected as the substrate, which is commonly used in biomedical implants in bone regeneration and cardiovascular stents because of its good biocompatibility and easy post-modification. The as-fabricated CuNPs-incorporated PCL membrane [PCL-(MI-hPG)-CuNPs] was confirmed with effective antibacterial performance via in vitro antibacterial tests against Staphylococcus aureus (S. aureus), Escherichia coli (E. coli), and multi-resistant E. coli. In addition, the in vitro results demonstrated that osteogenic property of PCL-(MI-hPG)-CuNPs was realized by upregulating the osteoblast-related gene expressions and protein activity. This study shows that antibacterial and osteogenic properties can be balanced in a surface coating by introducing CuNPs.}, language = {en} } @article{WittenbecherCuadratJohnstonetal.2022, author = {Wittenbecher, Clemens and Cuadrat, Rafael and Johnston, Luke and Eichelmann, Fabian and J{\"a}ger, Susanne and Kuxhaus, Olga and Prada, Marcela and Del Greco, Fabiola M. and Hicks, Andrew A. and Hoffman, Per and Krumsiek, Jan and Hu, Frank B. and Schulze, Matthias B.}, title = {Dihydroceramide- and ceramide-profiling provides insights into human cardiometabolic disease etiology}, series = {Nature communications}, volume = {13}, journal = {Nature communications}, publisher = {Nature Research}, address = {Berlin}, issn = {2041-1723}, doi = {10.1038/s41467-022-28496-1}, pages = {13}, year = {2022}, abstract = {Metabolic alterations precede cardiometabolic disease onset. Here we present ceramide- and dihydroceramide-profiling data from a nested case-cohort (type 2 diabetes [T2D, n = 775]; cardiovascular disease [CVD, n = 551]; random subcohort [n = 1137]) in the prospective EPIC-Potsdam study. We apply the novel NetCoupler-algorithm to link a data-driven (dihydro)ceramide network to T2D and CVD risk. Controlling for confounding by other (dihydro)ceramides, ceramides C18:0 and C22:0 and dihydroceramides C20:0 and C22:2 are associated with higher and ceramide C20:0 and dihydroceramide C26:1 with lower T2D risk. Ceramide C16:0 and dihydroceramide C22:2 are associated with higher CVD risk. Genome-wide association studies and Mendelian randomization analyses support a role of ceramide C22:0 in T2D etiology. Our results also suggest that (dh)ceramides partly mediate the putative adverse effect of high red meat consumption and benefits of coffee consumption on T2D risk. Thus, (dihydro)ceramides may play a critical role in linking genetic predisposition and dietary habits to cardiometabolic disease risk.}, language = {en} } @phdthesis{Brembach2024, author = {Brembach, Theresa-Charlotte}, title = {Regulators and effects of neutrophilic granulocytes in hidradenitis suppurativa}, school = {Universit{\"a}t Potsdam}, pages = {108, XV}, year = {2024}, language = {en} } @article{WilhelmiNeumannJaehnertetal.2021, author = {Wilhelmi, Ilka and Neumann, Alexander and J{\"a}hnert, Markus and Ouni, Meriem and Sch{\"u}rmann, Annette}, title = {Enriched alternative splicing in islets of diabetes-susceptible mice}, series = {International journal of molecular sciences}, volume = {22}, journal = {International journal of molecular sciences}, number = {16}, publisher = {Molecular Diversity Preservation International}, address = {Basel}, issn = {1422-0067}, doi = {10.3390/ijms22168597}, pages = {16}, year = {2021}, abstract = {Dysfunctional islets of Langerhans are a hallmark of type 2 diabetes (T2D). We hypothesize that differences in islet gene expression alternative splicing which can contribute to altered protein function also participate in islet dysfunction. RNA sequencing (RNAseq) data from islets of obese diabetes-resistant and diabetes-susceptible mice were analyzed for alternative splicing and its putative genetic and epigenetic modulators. We focused on the expression levels of chromatin modifiers and SNPs in regulatory sequences. We identified alternative splicing events in islets of diabetes-susceptible mice amongst others in genes linked to insulin secretion, endocytosis or ubiquitin-mediated proteolysis pathways. The expression pattern of 54 histones and chromatin modifiers, which may modulate splicing, were markedly downregulated in islets of diabetic animals. Furthermore, diabetes-susceptible mice carry SNPs in RNA-binding protein motifs and in splice sites potentially responsible for alternative splicing events. They also exhibit a larger exon skipping rate, e.g., in the diabetes gene Abcc8, which might affect protein function. Expression of the neuronal splicing factor Srrm4 which mediates inclusion of microexons in mRNA transcripts was markedly lower in islets of diabetes-prone compared to diabetes-resistant mice, correlating with a preferential skipping of SRRM4 target exons. The repression of Srrm4 expression is presumably mediated via a higher expression of miR-326-3p and miR-3547-3p in islets of diabetic mice. Thus, our study suggests that an altered splicing pattern in islets of diabetes-susceptible mice may contribute to an elevated T2D risk.}, language = {en} }