TY - JOUR A1 - Gerecke, Christian A1 - Schumacher, Fabian A1 - Berndzen, Alide A1 - Homann, Thomas A1 - Kleuser, Burkhard T1 - Vitamin C in combination with inhibition of mutant IDH1 synergistically activates TET enzymes and epigenetically modulates gene silencing in colon cancer cells JF - Epigenetics : the official journal of the DNA Methylation Society N2 - Mutations in the enzyme isocitrate dehydrogenase 1 (IDH1) lead to metabolic alterations and a sustained formation of 2-hydroxyglutarate (2-HG). 2-HG is an oncometabolite as it inhibits the activity of alpha-ketoglutarate-dependent dioxygenases such as ten-eleven translocation (TET) enzymes. Inhibitors of mutant IDH enzymes, like ML309, are currently tested in order to lower the levels of 2-HG. Vitamin C (VC) is an inducer of TET enzymes. To test a new therapeutic avenue of synergistic effects, the anti-neoplastic activity of inhibition of mutant IDH1 via ML309 in the presence of VC was investigated in the colon cancer cell line HCT116 IDH1(R132H/+) (harbouring a mutated IDH1 allele) and the parental cells HCT116 IDH1(+/+) (wild type IDH1). Measurement of the oncometabolite indicated a 56-fold higher content of 2-HG in mutated cells compared to wild type cells. A significant reduction of 2-HG was observed in mutated cells after treatment with ML 309, whereas VC produced only minimally changes of the oncometabolite. However, combinatorial treatment with both, ML309 and VC, in mutated cells induced pronounced reduction of 2-HG leading to levels comparable to those in wild type cells. The decreased level of 2-HG in mutated cells after combinatorial treatment was accompanied by an enhanced global DNA hydroxymethylation and an increased gene expression of certain tumour suppressors. Moreover, mutated cells showed an increased percentage of apoptotic cells after treatment with non-cytotoxic concentrations of ML309 and VC. These results suggest that combinatorial therapy is of interest for further investigation to rescue TET activity and treatment of IDH1/2 mutated cancers. KW - Vitamin C KW - epigenetics KW - IDH1 KW - TET KW - cancer cells Y1 - 2019 U6 - https://doi.org/10.1080/15592294.2019.1666652 SN - 1559-2294 SN - 1559-2308 VL - 15 IS - 3 SP - 307 EP - 322 PB - Taylor & Francis Group CY - Philadelphia ER - TY - JOUR A1 - Wienhold, Sandra-Maria A1 - Macri, Mario A1 - Nouailles, Geraldine A1 - Dietert, Kristina A1 - Gurtner, Corinne A1 - Gruber, Achim D. A1 - Heimesaat, Markus M. A1 - Lienau, Jasmin A1 - Schumacher, Fabian A1 - Kleuser, Burkhard A1 - Opitz, Bastian A1 - Suttorp, Norbert A1 - Witzenrath, Martin A1 - Müller-Redetzky, Holger C. T1 - Ventilator-induced lung injury is aggravated by antibiotic mediated microbiota depletion in mice JF - Critical Care N2 - BackgroundAntibiotic exposure alters the microbiota, which can impact the inflammatory immune responses. Critically ill patients frequently receive antibiotic treatment and are often subjected to mechanical ventilation, which may induce local and systemic inflammatory responses and development of ventilator-induced lung injury (VILI). The aim of this study was to investigate whether disruption of the microbiota by antibiotic therapy prior to mechanical ventilation affects pulmonary inflammatory responses and thereby the development of VILI.MethodsMice underwent 6-8weeks of enteral antibiotic combination treatment until absence of cultivable bacteria in fecal samples was confirmed. Control mice were housed equally throughout this period. VILI was induced 3 days after completing the antibiotic treatment protocol, by high tidal volume (HTV) ventilation (34ml/kg; positive end-expiratory pressure=2 cmH(2)O) for 4h. Differences in lung function, oxygenation index, pulmonary vascular leakage, macroscopic assessment of lung injury, and leukocyte and lymphocyte differentiation were assessed. Control groups of mice ventilated with low tidal volume and non-ventilated mice were analyzed accordingly.ResultsAntibiotic-induced microbiota depletion prior to HTV ventilation led to aggravation of VILI, as shown by increased pulmonary permeability, increased oxygenation index, decreased pulmonary compliance, enhanced macroscopic lung injury, and increased cytokine/chemokine levels in lung homogenates.ConclusionsDepletion of the microbiota by broad-spectrum antibiotics prior to HTV ventilation renders mice more susceptible to developing VILI, which could be clinically relevant for critically ill patients frequently receiving broad-spectrum antibiotics. KW - Broad-spectrum antibiotic therapy KW - Ventilator-induced lung injury KW - Microbiota Y1 - 2018 U6 - https://doi.org/10.1186/s13054-018-2213-8 SN - 1466-609X SN - 1364-8535 VL - 22 IS - 282 PB - BMC CY - London ER - TY - JOUR A1 - Grafen, Anika A1 - Schumacher, Fabian A1 - Chithelen, Janice A1 - Kleuser, Burkhard A1 - Beyersdorf, Niklas A1 - Schneider-Schaulies, Jürgen T1 - Use of Acid Ceramidase and Sphingosine Kinase Inhibitors as Antiviral Compounds Against Measles Virus Infection of Lymphocytes in vitro JF - Frontiers in Cell and Developmental Biology N2 - As structural membrane components and signaling effector molecules sphingolipids influence a plethora of host cell functions, and by doing so also the replication of viruses. Investigating the effects of various inhibitors of sphingolipid metabolism in primary human peripheral blood lymphocytes (PBL) and the human B cell line BJAB we found that not only the sphingosine kinase (SphK) inhibitor SKI-II, but also the acid ceramidase inhibitor ceranib-2 efficiently inhibited measles virus (MV) replication. Virus uptake into the target cells was not grossly altered by the two inhibitors, while titers of newly synthesized MV were reduced by approximately 1 log (90%) in PBL and 70-80% in BJAB cells. Lipidomic analyses revealed that in PBL SKI-II led to increased ceramide levels, whereas in BJAB cells ceranib-2 increased ceramides. SKI-II treatment decreased sphingosine-1-phosphate (S1P) levels in PBL and BJAB cells. Furthermore, we found that MV infection of lymphocytes induced a transient (0.5-6 h) increase in S1P, which was prevented by SKI-II. Investigating the effect of the inhibitors on the metabolic (mTORC1) activity we found that ceranib-2 reduced the phosphorylation of p70 S6K in PBL, and that both inhibitors, ceranib-2 and SKI-II, reduced the phosphorylation of p70 S6K in BJAB cells. As mTORC1 activity is required for efficient MV replication, this effect of the inhibitors is one possible antiviral mechanism. In addition, reduced intracellular S1P levels affect a number of signaling pathways and functions including Hsp90 activity, which was reported to be required for MV replication. Accordingly, we found that pharmacological inhibition of Hsp90 with the inhibitor 17-AAG strongly impaired MV replication in primary PBL. Thus, our data suggest that treatment of lymphocytes with both, acid ceramidase and SphK inhibitors, impair MV replication by affecting a number of cellular activities including mTORC1 and Hsp90, which alter the metabolic state of the cells causing a hostile environment for the virus. KW - measles virus KW - sphingolipids KW - acid ceramidase KW - acid ceramidase inhibitor ceranib-2 KW - sphingosine kinase KW - sphingosine kinase inhibitor SKI-II Y1 - 2019 U6 - https://doi.org/10.3389/fcell.2019.00218 SN - 2296-634X VL - 7 PB - Frontiers Research Foundation CY - Lausanne ER - TY - GEN A1 - Schwerbel, Kristin A1 - Kamitz, Anne A1 - Jaehnert, Markus A1 - Gottmann, P. A1 - Schumacher, Fabian A1 - Kleuser, Burkhard A1 - Haltenhof, T. A1 - Heyd, F. A1 - Roden, Michael A1 - Chadt, Alexandra A1 - Al-Hasani, Hadi A1 - Jonas, W. A1 - Vogel, Heike A1 - Schürmann, Annette T1 - Two immune-related GTPases prevent from hepatic fat accumulation by inducing autophagy T2 - Diabetologia : journal of the European Association for the Study of Diabetes (EASD) Y1 - 2018 SN - 0012-186X SN - 1432-0428 VL - 61 SP - S259 EP - S259 PB - Springer CY - New York ER - TY - JOUR A1 - Morris, Mackenzie C. A1 - Kassam, Farzaan A1 - Bercz, Aron A1 - Beckmann, Nadine A1 - Schumacher, Fabian A1 - Gulbins, Erich A1 - Makley, Amy T. A1 - Goodman, Michael D. T1 - The Role of Chemoprophylactic Agents in Modulating Platelet Aggregability After Traumatic Brain Injury JF - Journal of surgical research N2 - Background: The pathophysiology behind the subacute but persistent hypercoagulable state after traumatic brain injury (TBI) is poorly understood but contributes to morbidity induced by venous thromboembolism. Because platelets and their microvesicles have been hypothesized to play a role in post-traumatic hypercoagulability, administration of commonly used agents may ameliorate this coagulability. We hypothesized that utilization of aspirin, ketorolac, amitriptyline, unfractionated heparin, or enoxaparin would modulate the platelet aggregation response after TBI. Methods: Concussive TBI was induced by weight drop. Mice were then randomized to receive aspirin, ketorolac, amitriptyline, heparin, enoxaparin, or saline control at 2 and 8 h after TBI. Mice were sacrificed at 6 or 24 h after injury to determine coagulability by rotational thromboelastometry (ROTEM), platelet function testing with impedance aggregometry, and microvesicle enumeration. Platelet sphingolipid metabolites were analyzed by mass spectrometry. Results: ROTEM demonstrated increased platelet contribution to maximum clot firmness at 6 h after TBI in mice that received aspirin or amitriptyline, but this did not persist at 24 h. By contrast, adenosine diphosphate- and arachidonic acid-induced platelet aggregation at 6 h was significantly lower in mice receiving ketorolac, aspirin, and amitriptyline compared with mice receiving saline at 6 h after injury and only arachidonic acid-initiated platelet aggregation was decreased by aspirin at 24 h. There were no differences in microvesicle production at either time point. Platelet sphingosine-1-phosphate levels were decreased at 6 h in the group receiving amitriptyline and increased at 24 h along with platelet ceramide levels at 24 h in the amitriptyline group. Conclusion: After TBI, amitriptyline decreased platelet aggregability and increased contribution to clot in a manner similar to aspirin. The amitriptyline effects on platelet function and sphingolipid metabolites may represent a possible role of the acid sphingomyelinase in the hypercoagulability observed after injury. In addition, inhibition of platelet reactivity may be an underappreciated benefit of low molecular weight heparins, such as enoxaparin. (C) 2019 Elsevier Inc. All rights reserved. KW - Trauma KW - Traumatic brain injury KW - Venous thromboembolism KW - Chemoprophylaxis KW - Sphingolipids Y1 - 2019 U6 - https://doi.org/10.1016/j.jss.2019.06.022 SN - 0022-4804 SN - 1095-8673 VL - 244 SP - 1 EP - 8 PB - Elsevier CY - San Diego ER - TY - GEN A1 - Zoicas, Iulia A1 - Schumacher, Fabian A1 - Kleuser, Burkhard A1 - Reichel, Martin A1 - Gulbins, Erich A1 - Fejtova, Anna A1 - Kornhuber, Johannes A1 - Rhein, Cosima T1 - The forebrain-specific overexpression of acid sphingomyelinase induces depressive-like symptoms in mice T2 - Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe N2 - Human and murine studies identified the lysosomal enzyme acid sphingomyelinase (ASM) as a target for antidepressant therapy and revealed its role in the pathophysiology of major depression. In this study, we generated a mouse model with overexpression of Asm (Asm-tg(fb)) that is restricted to the forebrain to rule out any systemic effects of Asm overexpression on depressive-like symptoms. The increase in Asm activity was higher in male Asm-tg(fb) mice than in female Asm-tg(fb) mice due to the breeding strategy, which allows for the generation of wild-type littermates as appropriate controls. Asm overexpression in the forebrain of male mice resulted in a depressive-like phenotype, whereas in female mice, Asm overexpression resulted in a social anxiogenic-like phenotype. Ceramides in male Asm-tg(fb) mice were elevated specifically in the dorsal hippocampus. mRNA expression analyses indicated that the increase in Asm activity affected other ceramide-generating pathways, which might help to balance ceramide levels in cortical brain regions. This forebrain-specific mouse model offers a novel tool for dissecting the molecular mechanisms that play a role in the pathophysiology of major depression. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 1186 KW - Smpd1 KW - acid sphingomyelinase KW - forebrain KW - depressive-like behavior KW - anxiety-like behavior KW - ceramide Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-524368 SN - 1866-8372 IS - 5 ER - TY - JOUR A1 - Zoicas, Iulia A1 - Schumacher, Fabian A1 - Kleuser, Burkhard A1 - Reichel, Martin A1 - Gulbins, Erich A1 - Fejtova, Anna A1 - Kornhuber, Johannes A1 - Rhein, Cosima T1 - The forebrain-specific overexpression of acid sphingomyelinase induces depressive-like symptoms in mice JF - Cells N2 - Human and murine studies identified the lysosomal enzyme acid sphingomyelinase (ASM) as a target for antidepressant therapy and revealed its role in the pathophysiology of major depression. In this study, we generated a mouse model with overexpression of Asm (Asm-tg(fb)) that is restricted to the forebrain to rule out any systemic effects of Asm overexpression on depressive-like symptoms. The increase in Asm activity was higher in male Asm-tg(fb) mice than in female Asm-tg(fb) mice due to the breeding strategy, which allows for the generation of wild-type littermates as appropriate controls. Asm overexpression in the forebrain of male mice resulted in a depressive-like phenotype, whereas in female mice, Asm overexpression resulted in a social anxiogenic-like phenotype. Ceramides in male Asm-tg(fb) mice were elevated specifically in the dorsal hippocampus. mRNA expression analyses indicated that the increase in Asm activity affected other ceramide-generating pathways, which might help to balance ceramide levels in cortical brain regions. This forebrain-specific mouse model offers a novel tool for dissecting the molecular mechanisms that play a role in the pathophysiology of major depression. KW - Smpd1 KW - acid sphingomyelinase KW - forebrain KW - depressive-like behavior KW - anxiety-like behavior KW - ceramide Y1 - 2020 VL - 9 IS - 5 PB - MDPI CY - Basel ER - TY - JOUR A1 - Zabihi, Fatemeh A1 - Graff, Patrick A1 - Schumacher, Fabian A1 - Kleuser, Burkhard A1 - Hedtrich, Sarah A1 - Haag, Rainer T1 - Synthesis of poly(lactide-co-glycerol) as a biodegradable and biocompatible polymer with high loading capacity for dermal drug delivery JF - Nanoscale N2 - Due to the low cutaneous bioavailability of tacrolimus (TAC), penetration enhancers are used to improve its penetration into the skin. However, poor loading capacity, non-biodegradability, toxicity, and in some cases inefficient skin penetration are challenging issues that hamper their applications for the dermal TAC delivery. Here we present poly(lactide-co-glycerol) (PLG) as a water soluble, biodegradable, and biocompatible TAC-carrier with high loading capacity (14.5% w/w for TAC) and high drug delivery efficiencies into the skin. PLG was synthesized by cationic ring-opening copolymerization of a mixture of glycidol and lactide and showed 35 nm and 300 nm average sizes in aqueous solutions before and after loading of TAC, respectively. Delivery experiments on human skin, quantified by fluorescence microscopy and LC-MS/MS, showed a high ability for PLG to deposit Nile red and TAC into the stratum corneum and viable epidermis of skin in comparison with Protopic (R) (0.03% w/w, TAC ointment). The cutaneous distribution profile of delivered TAC proved that 80%, 16%, and 4% of the cutaneous drug level was deposited in the stratum corneum, viable epidermis, and upper dermis, respectively. TAC delivered by PLG was able to efficiently decrease the IL-2 and TSLP expressions in human skin models. Taking advantage of the excellent physicochemical and biological properties of PLG, it can be used for efficient dermal TAC delivery and potential treatment of inflammatory skin diseases. Y1 - 2018 U6 - https://doi.org/10.1039/c8nr05536j SN - 2040-3364 SN - 2040-3372 VL - 10 IS - 35 SP - 16848 EP - 16856 PB - Royal Society of Chemistry CY - Cambridge ER - TY - JOUR A1 - Seitz, Aaron P. A1 - Schumacher, Fabian A1 - Baker, Jennifer A1 - Soddemann, Matthias A1 - Wilker, Barbara A1 - Caldwell, Charles C. A1 - Gobble, Ryan M. A1 - Kamler, Markus A1 - Becker, Katrin Anne A1 - Beck, Sascha A1 - Kleuser, Burkhard A1 - Edwards, Michael J. A1 - Gulbins, Erich T1 - Sphingosine-coating of plastic surfaces prevents ventilator-associated pneumonia JF - Journal of molecular medicine N2 - Ventilator-associated pneumonia (VAP) is a major cause of morbidity and mortality in critically ill patients. Here, we employed the broad antibacterial effects of sphingosine to prevent VAP by developing a novel method of coating surfaces of endotracheal tubes with sphingosine and sphingosine analogs. Sphingosine and phytosphingosine coatings of endotracheal tubes prevent adherence and mediate killing of Pseudomonas aeruginosa, Acinetobacter baumannii, and Staphylococcus aureus, even in biofilms. Most importantly, sphingosine-coating of endotracheal tubes also prevented P. aeruginosa and S. aureus pneumonia in vivo. Coating of the tubes with sphingosine was stable, without obvious side effects on tracheal epithelial cells and did not induce inflammation. In summary, we describe a novel method to coat plastic surfaces and provide evidence for the application of sphingosine and phytosphingosine as novel antimicrobial coatings to prevent bacterial adherence and induce killing of pathogens on the surface of endotracheal tubes with potential to prevent biofilm formation and VAP.Key messagesNovel dip-coating method to coat plastic surfaces with lipids.Sphingosine and phytosphingosine as novel antimicrobial coatings on plastic surface.Sphingosine coatings of endotracheal tubes prevent bacterial adherence and biofilms.Sphingosine coatings of endotracheal tubes induce killing of pathogens.Sphingosine coatings of endotracheal tubes ventilator-associated pneumonia. KW - Coating KW - Plastic surfaces KW - Sphingosine KW - Ventilation KW - Acinetobacter baumannii KW - Pseudomonas aeruginosa KW - Staphylococcus aureus Y1 - 2019 U6 - https://doi.org/10.1007/s00109-019-01800-1 SN - 0946-2716 SN - 1432-1440 VL - 97 IS - 8 SP - 1195 EP - 1211 PB - Springer CY - Heidelberg ER - TY - JOUR A1 - Gutbier, Birgitt A1 - Schönrock, Stefanie M. A1 - Ehrler, Carolin A1 - Haberberger, Rainer A1 - Dietert, Kristina A1 - Gruber, Achim D. A1 - Kummer, Wolfgang A1 - Michalick, Laura A1 - Kuebler, Wolfgang M. A1 - Hocke, Andreas C. A1 - Szymanski, Kolja A1 - Letsiou, Eleftheria A1 - Lüth, Anja A1 - Schumacher, Fabian A1 - Kleuser, Burkhard A1 - Mitchell, Timothy J. A1 - Bertrams, Wilhelm A1 - Schmeck, Bernd A1 - Treue, Denise A1 - Klauschen, Frederick A1 - Bauer, Torsten T. A1 - Tönnies, Mario A1 - Weissmann, Norbert A1 - Hippenstiel, Stefan A1 - Suttorp, Norbert A1 - Witzenrath, Martin T1 - Sphingosine Kinase 1 Regulates Inflammation and Contributes to Acute Lung Injury in Pneumococcal Pneumonia via the Sphingosine-1-Phosphate Receptor 2 JF - Critical care medicine N2 - Objectives: Severe pneumonia may evoke acute lung injury, and sphingosine-1-phosphate is involved in the regulation of vascular permeability and immune responses. However, the role of sphingosine-1-phosphate and the sphingosine-1-phosphate producing sphingosine kinase 1 in pneumonia remains elusive. We examined the role of the sphingosine-1-phosphate system in regulating pulmonary vascular barrier function in bacterial pneumonia. Design: Controlled, in vitro, ex vivo, and in vivo laboratory study. Subjects: Female wild-type and SphK1-deficient mice, 8-10 weeks old. Human postmortem lung tissue, human blood-derived macrophages, and pulmonary microvascular endothelial cells. Interventions: Wild-type and SphK1-deficient mice were infected with Streptococcus pneumoniae. Pulmonary sphingosine-1-phosphate levels, messenger RNA expression, and permeability as well as lung morphology were analyzed. Human blood-derived macrophages and human pulmonary microvascular endothelial cells were infected with S. pneumoniae. Transcellular electrical resistance of human pulmonary microvascular endothelial cell monolayers was examined. Further, permeability of murine isolated perfused lungs was determined following exposition to sphingosine-1-phosphate and pneumolysin. Measurements and Main Results: Following S. pneumoniae infection, murine pulmonary sphingosine-1-phosphate levels and sphingosine kinase 1 and sphingosine-1-phosphate receptor 2 expression were increased. Pneumonia-induced lung hyperpermeability was reduced in SphK1(-/-) mice compared with wild-type mice. Expression of sphingosine kinase 1 in macrophages recruited to inflamed lung areas in pneumonia was observed in murine and human lungs. S. pneumoniae induced the sphingosine kinase 1/sphingosine-1-phosphate system in blood-derived macrophages and enhanced sphingosine-1-phosphate receptor 2 expression in human pulmonary microvascular endothelial cell in vitro. In isolated mouse lungs, pneumolysin-induced hyperpermeability was dose dependently and synergistically increased by sphingosine-1-phosphate. This sphingosine-1-phosphate-induced increase was reduced by inhibition of sphingosine-1-phosphate receptor 2 or its downstream effector Rho-kinase. Conclusions: Our data suggest that targeting the sphingosine kinase 1-/sphingosine-1-phosphate-/sphingosine-1-phosphate receptor 2-signaling pathway in the lung may provide a novel therapeutic perspective in pneumococcal pneumonia for prevention of acute lung injury. KW - acute lung injury KW - pneumococcal pneumonia KW - sphingosine kinase 1 KW - sphingosine-1-phosphate KW - sphingosine-1-phosphate receptor 2 Y1 - 2018 U6 - https://doi.org/10.1097/CCM.0000000000002916 SN - 0090-3493 SN - 1530-0293 VL - 46 IS - 3 SP - e258 EP - e267 PB - Lippincott Williams & Wilkins CY - Philadelphia ER - TY - JOUR A1 - Wigger, Dominik A1 - Schumacher, Fabian A1 - Schneider-Schaulies, Sibylle A1 - Kleuser, Burkhard T1 - Sphingosine 1-phosphate metabolism and insulin signaling JF - Cellular signalling N2 - Insulin is the main anabolic hormone secreted by 13-cells of the pancreas stimulating the assimilation and storage of glucose in muscle and fat cells. It modulates the postprandial balance of carbohydrates, lipids and proteins via enhancing lipogenesis, glycogen and protein synthesis and suppressing glucose generation and its release from the liver. Resistance to insulin is a severe metabolic disorder related to a diminished response of peripheral tissues to the insulin action and signaling. This leads to a disturbed glucose homeostasis that precedes the onset of type 2 diabetes (T2D), a disease reaching epidemic proportions. A large number of studies reported an association between elevated circulating fatty acids and the development of insulin resistance. The increased fatty acid lipid flux results in the accumulation of lipid droplets in a variety of tissues. However, lipid intermediates such as diacylglycerols and ceramides are also formed in response to elevated fatty acid levels. These bioactive lipids have been associated with the pathogenesis of insulin resistance. More recently, sphingosine 1-phosphate (S1P), another bioactive sphingolipid derivative, has also been shown to increase in T2D and obesity. Although many studies propose a protective role of S1P metabolism on insulin signaling in peripheral tissues, other studies suggest a causal role of S1P on insulin resistance. In this review, we critically summarize the current state of knowledge of S1P metabolism and its modulating role on insulin resistance. A particular emphasis is placed on S1P and insulin signaling in hepatocytes, skeletal muscle cells, adipocytes and pancreatic 13-cells. In particular, modulation of receptors and enzymes that regulate S1P metabolism can be considered as a new therapeutic option for the treatment of insulin resistance and T2D. KW - Insulin resistance KW - Type 2 diabetes KW - Sphingolipids KW - Hepatocytes KW - Adipocytes KW - Skeletal muscle cells Y1 - 2021 U6 - https://doi.org/10.1016/j.cellsig.2021.109959 SN - 0898-6568 SN - 1873-3913 VL - 82 PB - Elsevier Science CY - Amsterdam [u.a.] ER - TY - JOUR A1 - Speckmann, Bodo A1 - Schulz, Sarah A1 - Hiller, Franziska A1 - Hesse, Deike A1 - Schumacher, Fabian A1 - Kleuser, Burkhard A1 - Geisel, Juergen A1 - Obeid, Rima A1 - Grune, Tilman A1 - Kipp, Anna Patricia T1 - Selenium increases hepatic DNA methylation and modulates one-carbon metabolism in the liver of mice JF - The journal of nutritional biochemistry N2 - The average intake of the essential trace element selenium (Se) is below the recommendation in most European countries, possibly causing sub-optimal expression of selenoproteins. It is still unclear how a suboptimal Se status may affect health. To mimic this situation, mice were fed one of three physiologically relevant amounts of Se. We focused on the liver, the organ most sensitive to changes in the Se supply indicated by hepatic glutathione peroxidase activity. In addition, liver is the main organ for synthesis of methyl groups and glutathione via one-carbon metabolism. Accordingly, the impact of Se on global DNA methylation, methylation capacity, and gene expression was assessed. We observed higher global DNA methylation indicated by LINE1 methylation, and an increase of the methylation potential as indicated by higher S-adenosylmethionine (SAM)/S-adenosylhomocysteine (SAH) ratio and by elevated mRNA expression of serine hydroxymethyltransferase in both or either of the Se groups. Furthermore, increasing the Se supply resulted in higher plasma concentrations of triglycerides. Hepatic expression of glycolytic and lipogenic genes revealed consistent Se dependent up-regulation of glucokinase. The sterol regulatory element-binding transcription factor 1 (Srebf1) was also up-regulated by Se. Both effects were confirmed in primary hepatocytes. In contrast to the overall Se-dependent increase of methylation capacity, the up-regulation of Srebf1 expression was paralleled by reduced local methylation of a specific CpG site within the Srebf1 gene. Thus, we provided evidence that Se-dependent effects on lipogenesis involve epigenetic mechanisms. (C) 2017 The Authors. Published by Elsevier Inc. KW - Selenium KW - DNA methylation KW - Liver KW - Lipogenesis KW - Srebf1 Y1 - 2017 U6 - https://doi.org/10.1016/j.jnutbio.2017.07.002 SN - 0955-2863 SN - 1873-4847 VL - 48 SP - 112 EP - 119 PB - Elsevier CY - New York ER - TY - JOUR A1 - Börtlein, Charlene A1 - Schumacher, Fabian A1 - Kleuser, Burkhard A1 - Dölken, Lars A1 - Avota, Elita T1 - Role of Neutral Sphingomyelinase-2 (NSM 2) in the Control of T Cell Plasma Membrane Lipid Composition and Cholesterol Homeostasis JF - Frontiers in cell and developmental biology N2 - The activity of neutral sphingomyelinase-2 (NSM2) to catalyze the conversion of sphingomyelin (SM) to ceramide and phosphocholine at the cytosolic leaflet of plasma membrane (PM) is important in T cell receptor (TCR) signaling. We recently identified PKC zeta as a major NSM2 downstream effector which regulates microtubular polarization. It remained, however, unclear to what extent NSM2 activity affected overall composition of PM lipids and downstream effector lipids in antigen stimulated T cells. Here, we provide a detailed lipidomics analyses on PM fractions isolated from TCR stimulated wild type and NSM2 deficient (Delta NSM) Jurkat T cells. This revealed that in addition to that of sphingolipids, NSM2 depletion also affected concentrations of many other lipids. In particular, NSM2 ablation resulted in increase of lyso-phosphatidylcholine (LPC) and lyso-phosphatidylethanolamine (LPE) which both govern PM biophysical properties. Crucially, TCR dependent upregulation of the important T cell signaling lipid diacylglycerol (DAG), which is fundamental for activation of conventional and novel PKCs, was abolished in Delta NSM cells. Moreover, NSM2 activity was found to play an important role in PM cholesterol transport to the endoplasmic reticulum (ER) and production of cholesteryl esters (CE) there. Most importantly, CE accumulation was essential to sustain human T cell proliferation. Accordingly, inhibition of CE generating enzymes, the cholesterol acetyltransferases ACAT1/SOAT1 and ACAT2/SOAT2, impaired TCR driven expansion of both CD4(+) and CD8(+) T cells. In summary, our study reveals an important role of NSM2 in regulating T cell functions by its multiple effects on PM lipids and cholesterol homeostasis. KW - neutral sphingomyelinase-2 KW - T cell receptor KW - plasma membrane KW - lyso-phospholipids KW - diacylglycerol KW - cholesteryl ester Y1 - 2019 U6 - https://doi.org/10.3389/fcell.2019.00226 SN - 2296-634X VL - 7 PB - Frontiers Research Foundation CY - Lausanne ER - TY - JOUR A1 - Wanjiku, Barbara A1 - Yamamoto, Kenji A1 - Klossek, Andre A1 - Schumacher, Fabian A1 - Pischon, Hannah A1 - Mundhenk, Lars A1 - Rancan, Fiorenza A1 - Judd, Martyna M. A1 - Ahmed, Muniruddin A1 - Zoschke, Christian A1 - Kleuser, Burkhard A1 - Rühl, Eckart A1 - Schäfer-Korting, Monika T1 - Qualifying X-ray and Stimulated Raman Spectromicroscopy for Mapping Cutaneous Drug Penetration JF - Analytical chemistry N2 - Research on topical drug delivery relies on reconstructed human skin (RHS) in addition to ex vivo human and animal skin, each with specific physiological features. Here, we compared the penetration of dexamethasone from an ethanolic hydroxyethyl cellulose gel into ex vivo human skin, murine skin, and RHS. For comprehensive insights into skin morphology and penetration enhancing mechanisms, scanning transmission X-ray microscopy (STXM), liquid chromatography tandem mass spectrometry (LC-MS/MS), and stimulated Raman spectromicroscopy (SRS) were combined. STXM offers high spatial resolution with label-free drug detection and is therefore sensitive to tissue damage. Despite differences in sample preparation and data analysis, the amounts of dexamethasone in RHS, detected and quantified by STXM and LC-MS/MS, were very similar and increased during the first 100 min of exposure. SRS revealed interactions between the gel and the stratum corneum or, more specifically, its protein and lipid structures. Similar to both types of ex vivo skin, higher protein-to-lipid ratios within the stratum corneum of RHS indicated reduced lipid amounts after 30 min of ethanol exposure. Extended ethanol exposure led to a continued reduction of lipids in the ex vivo matrixes, while protein integrity appeared to be compromised in RHS, which led to declining protein signals. In conclusion, LC-MS/MS proved the predictive capability of STXM for label-free drug detection. Combining STXM with SRS precisely dissected the penetration enhancing effects of ethanol. Further studies on topical drug delivery should consider the potential of these complementary techniques. Y1 - 2019 U6 - https://doi.org/10.1021/acs.analchem.9b00519 SN - 0003-2700 SN - 1520-6882 VL - 91 IS - 11 SP - 7208 EP - 7214 PB - American Chemical Society CY - Washington ER - TY - JOUR A1 - Beckmann, Nadine A1 - Kadow, Stephanie A1 - Schumacher, Fabian A1 - Goethert, Joachim R. A1 - Kesper, Stefanie A1 - Draeger, Annette A1 - Schulz-Schaeffer, Walter J. A1 - Wang, Jiang A1 - Becker, Jan U. A1 - Kramer, Melanie A1 - Kuehn, Claudine A1 - Kleuser, Burkhard A1 - Becker, Katrin Anne A1 - Gulbins, Erich A1 - Carpinteiro, Alexander T1 - Pathological manifestations of Farber disease in a new mouse model JF - Biological chemistry N2 - Farber disease (FD) is a rare lysosomal storage disorder resulting from acid ceramidase deficiency and subsequent ceramide accumulation. No treatments are clinically available and affected patients have a severely shortened lifespan. Due to the low incidence, the pathogenesis of FD is still poorly understood. Here, we report a novel acid ceramidase mutant mouse model that enables the study of pathogenic mechanisms of FD and ceramide accumulation. Asah1(tmEx1) mice were generated by deletion of the acid ceramidase signal peptide sequence. The effects on lysosomal targeting and activity of the enzyme were assessed. Ceramide and sphingomyelin levels were quantified by liquid chromatography tandem-mass spectrometry (LC-MS/MS) and disease manifestations in several organ systems were analyzed by histology and biochemistry. We show that deletion of the signal peptide sequence disrupts lysosomal targeting and enzyme activity, resulting in ceramide and sphingomyelin accumulation. The affected mice fail to thrive and die early. Histiocytic infiltrations were observed in many tissues, as well as lung inflammation, liver fibrosis, muscular disease manifestations and mild kidney injury. Our new mouse model mirrors human FD and thus offers further insights into the pathogenesis of this disease. In the future, it may also facilitate the development of urgently needed therapies. KW - acid ceramidase KW - ceramide KW - Farber disease KW - lysosomal storage disorders Y1 - 2018 U6 - https://doi.org/10.1515/hsz-2018-0170 SN - 1431-6730 SN - 1437-4315 VL - 399 IS - 10 SP - 1183 EP - 1202 PB - De Gruyter CY - Berlin ER - TY - GEN A1 - Döge, Nadine A1 - Schumacher, Fabian A1 - Balzus, Benjamin A1 - Colombo, Miriam A1 - Hadam, Sabrina A1 - Rancan, Fiorenza A1 - Blume-Peytavi, Ulrike A1 - Kleuser, Burkhard A1 - Bodmeier, Roland A1 - Vogt, Annika T1 - Particle- based formulations and controlled skin barrier disruption have a signifi cant impact on the delivery and penetration kinetics of dexamethasone as assessed in an ex vivo microdialysis T2 - Journal der Deutschen Dermatologischen Gesellschaft N2 - Preclinical assessment of penetration not only in intact, but also in barrier‐disrupted skin is important to explore the surplus value of novel drug delivery systems, which can be specifically designed for diseased skin. Here, we characterized physical and chemical barrier disruption protocols for short‐term ex vivo skin cultures with regard to structural integrity, physiological and biological parameters. Further, we compared the penetration of dexamethasone (Dex) in different nanoparticle‐based formulations in stratum corneum, epidermis and dermis extracts of intact vs. barrier‐disrupted skin as well as by dermal microdialysis at 6, 12 and 24 hours after topical application. Dex was quantified by liquid‐chromatography ‐ tandem‐mass spectrometry (LC‐MS/MS). Simultaneously, we investigated the Dex efficacy by interleukin (IL) analysis. Tape‐stripping (TS) and 4 hours sodium lauryl sulfate 5 % (SLS) exposure were identified as highly effective barrier disruption methods assessed by reproducible transepidermal water loss (TEWL) changes and IL‐6/8 increase which was more pronounced in SLS‐treated skin. The barrier state has also a significant impact on the Dex penetration kinetics: for all formulations, TS highly increased dermal Dex concentration despite the fact that nanocrystals quickly and effectively penetrated both, intact and barrier‐disrupted skin reaching significantly higher dermal Dex concentration after 6 hours compared to Dex cream. The surplus value of encapsulation in ethyl cellulose nanocarriers could mostly be observed when applied on intact skin, in general showing a delayed Dex penetration. Estimation of cytokines was limited due to the trauma caused by probe insertion. In summary, ex vivo human skin is a highly interesting short‐term preclinical model for the analysis of penetration and efficacy of novel drug delivery systems. Y1 - 2017 SN - 1610-0379 SN - 1610-0387 VL - 15 SP - 182 EP - 182 PB - Wiley CY - Berlin ER - TY - CHAP A1 - Wiesner, Melanie A1 - Barknowitz, Gitte A1 - Florian, Simone A1 - Haack, Michael A1 - Lehmann, Carsten A1 - Lippmann, Doris A1 - Mewis, Inga A1 - Schumacher, Fabian A1 - Brigelius-Flohé, Regina A1 - Schreiner, Monika A1 - Glatt, Hansruedi T1 - Pak Choi Fed to Mice: Formation of DNA Adducts and Influence on Xenobiotic-Metabolizing Enzymes T2 - NAUNYN-SCHMIEDEBERGS ARCHIVES OF PHARMACOLOGY Y1 - 2015 SN - 0028-1298 SN - 1432-1912 VL - 388 SP - S68 EP - S68 PB - Springer CY - New York ER - TY - GEN A1 - Wigger, Dominik A1 - Gulbins, Erich A1 - Kleuser, Burkhard A1 - Schumacher, Fabian T1 - Monitoring the Sphingolipid de novo Synthesis by Stable-Isotope Labeling and Liquid Chromatography-Mass Spectrometry T2 - Postprints der Universität Potsdam Mathematisch-Naturwissenschaftliche Reihe N2 - Sphingolipids are a class of lipids that share a sphingoid base backbone. They exert various effects in eukaryotes, ranging from structural roles in plasma membranes to cellular signaling. De novo sphingolipid synthesis takes place in the endoplasmic reticulum (ER), where the condensation of the activated C₁₆ fatty acid palmitoyl-CoA and the amino acid L-serine is catalyzed by serine palmitoyltransferase (SPT). The product, 3-ketosphinganine, is then converted into more complex sphingolipids by additional ER-bound enzymes, resulting in the formation of ceramides. Since sphingolipid homeostasis is crucial to numerous cellular functions, improved assessment of sphingolipid metabolism will be key to better understanding several human diseases. To date, no assay exists capable of monitoring de novo synthesis sphingolipid in its entirety. Here, we have established a cell-free assay utilizing rat liver microsomes containing all the enzymes necessary for bottom-up synthesis of ceramides. Following lipid extraction, we were able to track the different intermediates of the sphingolipid metabolism pathway, namely 3-ketosphinganine, sphinganine, dihydroceramide, and ceramide. This was achieved by chromatographic separation of sphingolipid metabolites followed by detection of their accurate mass and characteristic fragmentations through high-resolution mass spectrometry and tandem-mass spectrometry. We were able to distinguish, unequivocally, between de novo synthesized sphingolipids and intrinsic species, inevitably present in the microsome preparations, through the addition of stable isotope-labeled palmitate-d₃ and L-serine-d₃. To the best of our knowledge, this is the first demonstration of a method monitoring the entirety of ER-associated sphingolipid biosynthesis. Proof-of-concept data was provided by modulating the levels of supplied cofactors (e.g., NADPH) or the addition of specific enzyme inhibitors (e.g., fumonisin B₁). The presented microsomal assay may serve as a useful tool for monitoring alterations in sphingolipid de novo synthesis in cells or tissues. Additionally, our methodology may be used for metabolism studies of atypical substrates – naturally occurring or chemically tailored – as well as novel inhibitors of enzymes involved in sphingolipid de novo synthesis. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 800 KW - sphingolipid de novo synthesis KW - serine palmitoyltransferase KW - mass spectrometry KW - stable-isotope labeling KW - ceramides Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-441158 SN - 1866-8372 IS - 800 ER - TY - JOUR A1 - Wigger, Dominik A1 - Gulbins, Erich A1 - Kleuser, Burkhard A1 - Schumacher, Fabian T1 - Monitoring the Sphingolipid de novo Synthesis by Stable-Isotope Labeling and Liquid Chromatography-Mass Spectrometry JF - Frontiers in Cell and Developmental Biology N2 - Sphingolipids are a class of lipids that share a sphingoid base backbone. They exert various effects in eukaryotes, ranging from structural roles in plasma membranes to cellular signaling. De novo sphingolipid synthesis takes place in the endoplasmic reticulum (ER), where the condensation of the activated C₁₆ fatty acid palmitoyl-CoA and the amino acid L-serine is catalyzed by serine palmitoyltransferase (SPT). The product, 3-ketosphinganine, is then converted into more complex sphingolipids by additional ER-bound enzymes, resulting in the formation of ceramides. Since sphingolipid homeostasis is crucial to numerous cellular functions, improved assessment of sphingolipid metabolism will be key to better understanding several human diseases. To date, no assay exists capable of monitoring de novo synthesis sphingolipid in its entirety. Here, we have established a cell-free assay utilizing rat liver microsomes containing all the enzymes necessary for bottom-up synthesis of ceramides. Following lipid extraction, we were able to track the different intermediates of the sphingolipid metabolism pathway, namely 3-ketosphinganine, sphinganine, dihydroceramide, and ceramide. This was achieved by chromatographic separation of sphingolipid metabolites followed by detection of their accurate mass and characteristic fragmentations through high-resolution mass spectrometry and tandem-mass spectrometry. We were able to distinguish, unequivocally, between de novo synthesized sphingolipids and intrinsic species, inevitably present in the microsome preparations, through the addition of stable isotope-labeled palmitate-d₃ and L-serine-d₃. To the best of our knowledge, this is the first demonstration of a method monitoring the entirety of ER-associated sphingolipid biosynthesis. Proof-of-concept data was provided by modulating the levels of supplied cofactors (e.g., NADPH) or the addition of specific enzyme inhibitors (e.g., fumonisin B₁). The presented microsomal assay may serve as a useful tool for monitoring alterations in sphingolipid de novo synthesis in cells or tissues. Additionally, our methodology may be used for metabolism studies of atypical substrates – naturally occurring or chemically tailored – as well as novel inhibitors of enzymes involved in sphingolipid de novo synthesis. KW - sphingolipid de novo synthesis KW - serine palmitoyltransferase KW - mass spectrometry KW - stable-isotope labeling KW - ceramides Y1 - 2019 U6 - https://doi.org/10.3389/fcell.2019.00210 SN - 2296-634X VL - 7 PB - Frontiers Media CY - Lausanne ER - TY - JOUR A1 - Neuber, Corinna A1 - Schumacher, Fabian A1 - Gulbins, Erich A1 - Kleuser, Burkhard T1 - Method to simultaneously determine the sphingosine 1-phosphate breakdown product (2E)-hexadecenal and its fatty acid derivatives using isotope-dilution HPLC-electrospray ionization-quadrupole/time-of-flight mass spectrometry JF - Analytical chemistry N2 - Sphingosine 1-phosphate (S1P), a bioactive lipid involved in various physiological processes, can be irreversibly degraded by the membrane-bound S1P lyase (S1PL) yielding (2E)-hexadecenal and phosphoethanolamine. It is discussed that (2E)-hexadecenal is further oxidized to (2E)-hexadecenoic acid by the long-chain fatty aldehyde dehydrogenase ALDH3A2 (also known as FALDH) prior to activation via coupling to coenzyme A (CoA). Inhibition or defects in these enzymes, S1PL or FALDH, result in severe immunological disorders or the Sjogren-Larsson syndrome, respectively. Hence, it is of enormous importance to simultaneously determine the S1P breakdown product (2E)-hexadecenal and its fatty acid metabolites in biological samples. However, no method is available so far. Here, we present a sensitive and selective isotope-dilution high performance liquid chromatographyelectrospray ionizationquadrupole/time-of-flight mass spectrometry method for simultaneous quantification of (2E)-hexadecenal and its fatty acid metabolites following derivatization with 2-diphenylacetyl-1,3-indandione-1-hydrazone and 1-ethyl-3-(3-(dimethylamino)propyl)carbodiimide. Optimized conditions for sample derivatization, chromatographic separation, and MS/MS detection are presented as well as an extensive method validation. Finally, our method was successfully applied to biological samples. We found that (2E)-hexadecenal is almost quantitatively oxidized to (2E)-hexadecenoic acid, that is further activated as verified by cotreatment of HepG2 cell lysates with (2E)-hexadecenal and the acyl-CoA synthetase inhibitor triacsin C. Moreover, incubations of cell lysates with deuterated (2E)-hexadecenal revealed that no hexadecanoic acid is formed from the aldehyde. Thus, our method provides new insights into the sphingolipid metabolism and will be useful to investigate diseases known for abnormalities in long-chain fatty acid metabolism, e.g., the Sjogren-Larsson syndrome, in more detail. Y1 - 2014 U6 - https://doi.org/10.1021/ac501677y SN - 0003-2700 SN - 1520-6882 VL - 86 IS - 18 SP - 9065 EP - 9073 PB - American Chemical Society CY - Washington ER - TY - JOUR A1 - Castaño Martínez, María Teresa A1 - Schumacher, Fabian A1 - Schumacher, Silke A1 - Kochlik, Bastian Max A1 - Weber, Daniela A1 - Grune, Tilman A1 - Biemann, Ronald A1 - McCann, Adrian A1 - Abraham, Klaus A1 - Weikert, Cornelia A1 - Kleuse, Burkhard A1 - Schürmann, Annette A1 - Laeger, Thomas T1 - Methionine restriction prevents onset of type 2 diabetes in NZO mice JF - The FASEB journal : the official journal of the Federation of American Societies for Experimental Biology N2 - Dietary methionine restriction (MR) is well known to reduce body weight by increasing energy expenditure (EE) and insulin sensitivity. An elevated concentration of circulating fibroblast growth factor 21 (FGF21) has been implicated as a potential underlying mechanism. The aims of our study were to test whether dietary MR in the context of a high-fat regimen protects against type 2 diabetes in mice and to investigate whether vegan and vegetarian diets, which have naturally low methionine levels, modulate circulating FGF21 in humans. New Zealand obese (NZO) mice, a model for polygenic obesity and type 2 diabetes, were placed on isocaloric high-fat diets (protein, 16 kcal%; carbohydrate, 52 kcal%; fat, 32 kcal%) that provided methionine at control (Con; 0.86% methionine) or low levels (0.17%) for 9 wk. Markers of glucose homeostasis and insulin sensitivity were analyzed. Among humans, low methionine intake and circulating FGF21 levels were investigated by comparing a vegan and a vegetarian diet to an omnivore diet and evaluating the effect of a short-term vegetarian diet on FGF21 induction. In comparison with the Con group, MR led to elevated plasma FGF21 levels and prevented the onset of hyperglycemia in NZO mice. MR-fed mice exhibited increased insulin sensitivity, higher plasma adiponectin levels, increased EE, and up-regulated expression of thermogenic genes in subcutaneous white adipose tissue. Food intake and fat mass did not change. Plasma FGF21 levels were markedly higher in vegan humans compared with omnivores, and circulating FGF21 levels increased significantly in omnivores after 4 d on a vegetarian diet. These data suggest that MR induces FGF21 and protects NZO mice from high-fat diet-induced glucose intolerance and type 2 diabetes. The normoglycemic phenotype in vegans and vegetarians may be caused by induced FGF21. MR akin to vegan and vegetarian diets in humans may offer metabolic benefits via increased circulating levels of FGF21 and merits further investigation.-Castano-Martinez, T., Schumacher, F., Schumacher, S., Kochlik, B., Weber, D., Grune, T., Biemann, R., McCann, A., Abraham, K., Weikert, C., Kleuser, B., Schurmann, A., Laeger, T. Methionine restriction prevents onset of type 2 diabetes in NZO mice. KW - energy expenditure KW - hyperglycemia KW - obesity KW - vegan KW - vegetarian Y1 - 2019 U6 - https://doi.org/10.1096/fj.201900150R SN - 0892-6638 SN - 1530-6860 VL - 33 IS - 6 SP - 7092 EP - 7102 PB - Federation of American Societies for Experimental Biology CY - Bethesda ER - TY - JOUR A1 - Derakhshani, Shaghayegh A1 - Kurz, Andreas A1 - Japtok, Lukasz A1 - Schumacher, Fabian A1 - Pilgram, Lisa A1 - Steinke, Maria A1 - Kleuser, Burkhard A1 - Sauer, Markus A1 - Schneider-Schaulies, Sibylle A1 - Avota, Elita T1 - Measles Virus Infection Fosters Dendritic Cell Motility in a 3D Environment to Enhance Transmission to Target Cells in the Respiratory Epithelium JF - Frontiers in immunology N2 - Transmission of measles virus (MV) from dendritic to airway epithelial cells is considered as crucial to viral spread late in infection. Therefore, pathways and effectors governing this process are promising targets for intervention. To identify these, we established a 3D respiratory tract model where MV transmission by infected dendritic cells (DCs) relied on the presence of nectin-4 on H358 lung epithelial cells. Access to recipient cells is an important prerequisite for transmission, and we therefore analyzed migration of MV-exposed DC cultures within the model. Surprisingly, enhanced motility toward the epithelial layer was observed for MV-infected DCs as compared to their uninfected siblings. This occurred independently of factors released from H358 cells indicating that MV infection triggered cytoskeletal remodeling associated with DC polarization enforced velocity. Accordingly, the latter was also observed for MV-infected DCs in collagen matrices and was particularly sensitive to ROCK inhibition indicating infected DCs preferentially employed the amoeboid migration mode. This was also implicated by loss of podosomes and reduced filopodial activity both of which were retained in MV-exposed uninfected DCs. Evidently, sphingosine kinase (SphK) and sphingosine-1-phosphate (S1P) as produced in response to virus-infection in DCs contributed to enhanced velocity because this was abrogated upon inhibition of sphingosine kinase activity. These findings indicate that MV infection promotes a push-and-squeeze fast amoeboid migration mode via the SphK/S1P system characterized by loss of filopodia and podosome dissolution. Consequently, this enables rapid trafficking of virus toward epithelial cells during viral exit. KW - dendritic cell KW - cell migration KW - measles virus KW - 3D tissue model KW - sphingosine-1-phosphate Y1 - 2019 U6 - https://doi.org/10.3389/fimmu.2019.01294 SN - 1664-3224 VL - 10 PB - Frontiers Research Foundation CY - Lausanne ER - TY - JOUR A1 - Neuber, Corinna A1 - Schumacher, Fabian A1 - Gulbins, Erich A1 - Kleuser, Burkhard T1 - Mass Spectrometric Determination of Fatty Aldehydes Exemplified by Monitoring the Oxidative Degradation of (2E)-Hexadecenal in HepG2 Cell Lysates JF - Lipidomics N2 - Within the last few decades, liquid chromatography-mass spectrometry (LC-MS) has become a preferred method for manifold issues in analytical biosciences, given its high selectivity and sensitivity. However, the analysis of fatty aldehydes, which are important components of cell metabolism, remains challenging. Usually, chemical derivatization prior to MS detection is required to enhance ionization efficiency. In this regard, the coupling of fatty aldehydes to hydrazines like 2,4-dinitrophenylhydrazine (DNPH) is a common approach. Additionally, hydrazones readily react with fatty aldehydes to form stable derivatives, which can be easily separated using high-performance liquid chromatography (HPLC) and subsequently detected by MS. Here, we exemplarily present the quantification of the long-chain fatty aldehyde (2E)-hexadecenal, a break-down product of the bioactive lipid sphingosine 1-phosphate (S1P), after derivatization with 2-diphenylacetyl-1,3-indandione-1-hydrazone (DAIH) via isotope-dilution HPLC-electrospray ionization-quadrupole/time-of-flight (ESI-QTOF) MS. Moreover, we show that the addition of N-(3-dimethylaminopropyl)-N′-ethylcarbodiimide hydrochloride (EDC hydrochloride) as a coupling agent allows for simultaneous determination of fatty aldehydes and fatty acids as DAIH derivatives. Taking advantage of this, we describe in detail how to monitor the degradation of (2E)-hexadecenal and the concurrent formation of its oxidation product (2E)-hexadecenoic acid in lysates of human hepatoblastoma (HepG2) cells within this chapter. KW - (2E)-hexadecenal KW - (2E)-hexadecenoic acid KW - Sphingosine 1-phosphate KW - Derivatization KW - DAIH KW - EDC KW - Isotope-dilution KW - HPLC-ESI-QTOF Y1 - 2017 SN - 978-1-4939-6946-3 SN - 978-1-4939-6944-9 U6 - https://doi.org/10.1007/978-1-4939-6946-3_10 SN - 0893-2336 SN - 1940-6045 VL - 125 SP - 147 EP - 158 PB - Humana Press CY - Totowa ER - TY - JOUR A1 - Fayyaz, Susann A1 - Japtok, Lukasz A1 - Schumacher, Fabian A1 - Wigger, Dominik A1 - Schulz, Tim Julius A1 - Haubold, Kathrin A1 - Gulbins, Erich A1 - Völler, Heinz A1 - Kleuser, Burkhard T1 - Lysophosphatidic acid inhibits insulin signaling in primary rat hepatocytes via the LPA(3) receptor subtype and is increased in obesity JF - Cellular physiology and biochemistry : international journal of experimental cellular physiology, biochemistry and pharmacology N2 - Background/Aims: Obesity is a main risk factor for the development of hepatic insulin resistance and it is accompanied by adipocyte hypertrophy and an elevated expression of different adipokines such as autotaxin (ATX). ATX converts lysophosphatidylcholine to lysophosphatidic acid (LPA) and acts as the main producer of extracellular LPA. This bioactive lipid regulates a broad range of physiological and pathological responses by activation of LPA receptors (LPA1-6). Methods: The activation of phosphatidylinositide 3-kinases (PI3K) signaling (Akt and GSK-3ß) was analyzed via western blotting in primary rat hepatocytes. Incorporation of glucose into glycogen was measured by using radio labeled glucose. Real-time PCR analysis and pharmacological modulation of LPA receptors were performed. Human plasma LPA levels of obese (BMI > 30, n = 18) and normal weight individuals (BMI 18.5-25, n = 14) were analyzed by liquid chromatography tandem-mass spectrometry (LC-MS/MS). Results: Pretreatment of primary hepatocytes with LPA resulted in an inhibition of insulin-mediated Gck expression, PI3K activation and glycogen synthesis. Pharmacological approaches revealed that the LPA3-receptor subtype is responsible for the inhibitory effect of LPA on insulin signaling. Moreover, human plasma LPA concentrations (16: 0 LPA) of obese participants (BMI > 30) are significantly elevated in comparison to normal weight individuals (BMI 18.5-25). Conclusion: LPA is able to interrupt insulin signaling in primary rat hepatocytes via the LPA3 receptor subtype. Moreover, the bioactive lipid LPA (16: 0) is increased in obesity. KW - Lysophosphatidic acid KW - Insulin signaling KW - Adipose tissue KW - Autotaxin KW - Hepatic insulin resistance KW - LPA(3) receptor subtype Y1 - 2017 U6 - https://doi.org/10.1159/000480470 SN - 1015-8987 SN - 1421-9778 VL - 43 SP - 445 EP - 456 PB - Karger CY - Basel ER - TY - GEN A1 - Chakraborty, Sudipta A1 - Chen, Pan A1 - Bornhorst, Julia A1 - Schwerdtle, Tanja A1 - Schumacher, Fabian A1 - Kleuser, Burkhard A1 - Bowman, Aaron B. A1 - Aschner, Michael A. T1 - Loss of pdr-1/parkin influences Mn homeostasis through altered ferroportin expression in C. elegans N2 - Overexposure to the essential metal manganese (Mn) can result in an irreversible condition known as manganism that shares similar pathophysiology with Parkinson's disease (PD), including dopaminergic (DAergic) cell loss that leads to motor and cognitive impairments. However, the mechanisms behind this neurotoxicity and its relationship with PD remain unclear. Many genes confer risk for autosomal recessive, early-onset PD, including the parkin/PARK2 gene that encodes for the E3 ubiquitin ligase Parkin. Using Caenorhabditis elegans (C. elegans) as an invertebrate model that conserves the DAergic system, we previously reported significantly increased Mn accumulation in pdr-1/parkin mutants compared to wildtype (WT) animals. For the current study, we hypothesize that this enhanced accumulation is due to alterations in Mn transport in the pdr-1 mutants. While no change in mRNA expression of the major Mn importer proteins (smf-1-3) was found in pdr-1 mutants, significant downregulation in mRNA levels of the putative Mn exporter ferroportin (fpn-1.1) was observed. Using a strain overexpressing fpn-1.1 in worms lacking pdr-1, we show evidence for attenuation of several endpoints of Mn-induced toxicity, including survival, metal accumulation, mitochondrial copy number and DAergic integrity, compared to pdr-1 mutants alone. These changes suggest a novel role of pdr-1 in modulating Mn export through altered transporter expression, and provides further support of metal dyshomeostasis as a component of Parkinsonism pathophysiology. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 290 Y1 - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-99508 ER - TY - JOUR A1 - Chakraborty, Sudipta A1 - Chen, Pan A1 - Bornhorst, Julia A1 - Schwerdtle, Tanja A1 - Schumacher, Fabian A1 - Kleuser, Burkhard A1 - Bowman, Aaron B. A1 - Aschner, Michael A. T1 - Loss of pdr-1/parkin influences Mn homeostasis through altered ferroportin expression in C-elegans JF - Metallomics : integrated biometal science Y1 - 2015 U6 - https://doi.org/10.1039/c5mt00052a SN - 1756-5901 SN - 1756-591X VL - 7 IS - 5 SP - 847 EP - 856 PB - Royal Society of Chemistry CY - Cambridge ER - TY - JOUR A1 - Samaha, Doaa A1 - Hamdo, Housam H. A1 - Cong, Xiaojing A1 - Schumacher, Fabian A1 - Banhart, Sebastian A1 - Aglar, Öznur A1 - Möller, Heiko Michael A1 - Heuer, Dagmar A1 - Kleuser, Burkhard A1 - Saied, Essa M. A1 - Arenz, Christoph T1 - Liposomal FRET assay identifies potent drug-like inhibitors of the Ceramide Transport Protein (CERT) JF - Chemistry - a European journal N2 - Ceramide transfer protein (CERT) mediates non-vesicular transfer of ceramide from endoplasmic reticulum to Golgi apparatus and thus catalyzes the rate-limiting step of sphingomyelin biosynthesis. Usually, CERT ligands are evaluated in tedious binding assays or non-homogenous transfer assays using radiolabeled ceramides. Herein, a facile and sensitive assay for CERT, based on Forster resonance energy transfer (FRET), is presented. To this end, we mixed donor and acceptor vesicles, each containing a different fluorescent ceramide species. By CERT-mediated transfer of fluorescent ceramide, a FRET system was established, which allows readout in 96-well plate format, despite the high hydrophobicity of the components. Screening of a 2 000 compound library resulted in two new potent CERT inhibitors. One is approved for use in humans and one is approved for use in animals. Evaluation of cellular activity by quantitative mass spectrometry and confocal microscopy showed inhibition of ceramide trafficking and sphingomyelin biosynthesis. KW - enzyme assays KW - Forster resonance energy transfer (FRET) KW - liposomes KW - sphingolipids KW - transport proteins Y1 - 2020 U6 - https://doi.org/10.1002/chem.202003283 SN - 0947-6539 SN - 1521-3765 VL - 26 IS - 70 SP - 16616 EP - 16621 PB - Wiley-VCH CY - Weinheim ER - TY - JOUR A1 - Meiners, Jana A1 - Palmieri, Vittoria A1 - Klopfleisch, Robert A1 - Ebel, Jana-Fabienne A1 - Japtok, Lukasz A1 - Schumacher, Fabian A1 - Yusuf, Ayan Mohamud A1 - Becker, Katrin Anne A1 - Zöller, Julia A1 - Hose, Matthias A1 - Kleuser, Burkhard A1 - Hermann, Dirk Matthias A1 - Kolesnick, Richard N. A1 - Buer, Jan A1 - Hansen, Wiebke A1 - Westendorf, Astrid M. T1 - Intestinal acid sphingomyelinase protects from severe Pathogen-Driven Colitis JF - Frontiers in immunology N2 - Inflammatory diseases of the gastrointestinal tract are emerging as a global problem with increased evidence and prevalence in numerous countries. A dysregulated sphingolipid metabolism occurs in patients with ulcerative colitis and is discussed to contribute to its pathogenesis. In the present study, we determined the impact of acid sphingomyelinase (Asm), which catalyzes the hydrolysis of sphingomyelin to ceramide, on the course of Citrobacter (C.) rodentium-driven colitis. C. rodentium is an enteric pathogen and induces colonic inflammation very similar to the pathology in patients with ulcerative colitis. We found that mice with Asm deficiency or Asm inhibition were strongly susceptible to C. rodentium infection. These mice showed increased levels of C. rodentium in the feces and were prone to bacterial spreading to the systemic organs. In addition, mice lacking Asm activity showed an uncontrolled inflammatory T(h)1 and T(h)17 response, which was accompanied by a stronger colonic pathology compared to infected wild type mice. These findings identified Asm as an essential regulator of mucosal immunity to the enteric pathogen C. rodentium. KW - Citrobacter rodentium KW - colitis KW - acid sphingomyelinase KW - amitriptyline KW - T(h)1 KW - T(h)17 Y1 - 2019 U6 - https://doi.org/10.3389/fimmu.2019.01386 SN - 1664-3224 VL - 10 PB - Frontiers Research Foundation CY - Lausanne ER - TY - JOUR A1 - Gronke, Konrad A1 - Hernandez, Pedro P. A1 - Zimmermann, Jakob A1 - Klose, Christoph S. N. A1 - Kofoed-Branzk, Michael A1 - Guendel, Fabian A1 - Witkowski, Mario A1 - Tizian, Caroline A1 - Amann, Lukas A1 - Schumacher, Fabian A1 - Glatt, Hansruedi A1 - Triantafyllopoulou, Antigoni A1 - Diefenbach, Andreas T1 - Interleukin-22 protects intestinal stem cells against genotoxic stress JF - Nature : the international weekly journal of science N2 - Environmental genotoxic factors pose a challenge to the genomic integrity of epithelial cells at barrier surfaces that separate host organisms from the environment. They can induce mutations that, if they occur in epithelial stem cells, contribute to malignant transformation and cancer development1,2,3. Genome integrity in epithelial stem cells is maintained by an evolutionarily conserved cellular response pathway, the DNA damage response (DDR). The DDR culminates in either transient cell-cycle arrest and DNA repair or elimination of damaged cells by apoptosis4,5. Here we show that the cytokine interleukin-22 (IL-22), produced by group 3 innate lymphoid cells (ILC3) and γδ T cells, is an important regulator of the DDR machinery in intestinal epithelial stem cells. Using a new mouse model that enables sporadic inactivation of the IL-22 receptor in colon epithelial stem cells, we demonstrate that IL-22 is required for effective initiation of the DDR following DNA damage. Stem cells deprived of IL-22 signals and exposed to carcinogens escaped DDR-controlled apoptosis, contained more mutations and were more likely to give rise to colon cancer. We identified metabolites of glucosinolates, a group of phytochemicals contained in cruciferous vegetables, to be a widespread source of genotoxic stress in intestinal epithelial cells. These metabolites are ligands of the aryl hydrocarbon receptor (AhR)6, and AhR-mediated signalling in ILC3 and γδ T cells controlled their production of IL-22. Mice fed with diets depleted of glucosinolates produced only very low levels of IL-22 and, consequently, the DDR in epithelial cells of mice on a glucosinolate-free diet was impaired. This work identifies a homeostatic network protecting stem cells against challenge to their genome integrity by AhR-mediated ‘sensing’ of genotoxic compounds from the diet. AhR signalling, in turn, ensures on-demand production of IL-22 by innate lymphocytes directly regulating components of the DDR in epithelial stem cells. Y1 - 2019 U6 - https://doi.org/10.1038/s41586-019-0899-7 SN - 0028-0836 SN - 1476-4687 VL - 566 IS - 7743 SP - 249 EP - 253 PB - Nature Publ. Group CY - London ER - TY - JOUR A1 - Rakers, Christin A1 - Schumacher, Fabian A1 - Meinl, Walter A1 - Glatt, Hansruedi A1 - Kleuser, Burkhard A1 - Wolber, Gerhard T1 - In Silico Prediction of Human Sulfotransferase 1E1 Activity Guided by Pharmacophores from Molecular Dynamics Simulations JF - The journal of biological chemistry N2 - Acting during phase II metabolism, sulfotransferases (SULTs) serve detoxification by transforming a broad spectrum of compounds from pharmaceutical, nutritional, or environmental sources into more easily excretable metabolites. However, SULT activity has also been shown to promote formation of reactive metabolites that may have genotoxic effects. SULT subtype 1E1 (SULT1E1) was identified as a key player in estrogen homeostasis, which is involved in many physiological processes and the pathogenesis of breast and endometrial cancer. The development of an in silico prediction model for SULT1E1 ligands would therefore support the development of metabolically inert drugs and help to assess health risks related to hormonal imbalances. Here, we report on a novel approach to develop a model that enables prediction of substrates and inhibitors of SULT1E1. Molecular dynamics simulations were performed to investigate enzyme flexibility and sample protein conformations. Pharmacophores were developed that served as a cornerstone of the model, and machine learning techniques were applied for prediction refinement. The prediction model was used to screen the DrugBank (a database of experimental and approved drugs): 28% of the predicted hits were reported in literature as ligands of SULT1E1. From the remaining hits, a selection of nine molecules was subjected to biochemical assay validation and experimental results were in accordance with the in silico prediction of SULT1E1 inhibitors and substrates, thus affirming our prediction hypotheses. KW - drug design KW - drug metabolism KW - liver metabolism KW - molecular dynamics KW - molecular modeling KW - sulfotransferase Y1 - 2016 U6 - https://doi.org/10.1074/jbc.M115.685610 SN - 0021-9258 SN - 1083-351X VL - 291 SP - 58 EP - 71 PB - American Society for Biochemistry and Molecular Biology CY - Bethesda ER - TY - JOUR A1 - Gohlke, Sabrina A1 - Zagoriy, Vyacheslav A1 - Inostroza, Alvaro Cuadros A1 - Meret, Michael A1 - Mancini, Carola A1 - Japtok, Lukasz A1 - Schumacher, Fabian A1 - Kuhlow, Doreen A1 - Graja, Antonia A1 - Stephanowitz, Heike A1 - Jähnert, Markus A1 - Krause, Eberhard A1 - Wernitz, Andreas A1 - Petzke, Klaus-Juergen A1 - Schürmann, Annette A1 - Kleuser, Burkhard A1 - Schulz, Tim Julius T1 - Identification of functional lipid metabolism biomarkers of brown adipose tissue aging JF - Molecular Metabolism N2 - Objective: Aging is accompanied by loss of brown adipocytes and a decline in their thermogenic potential, which may exacerbate the development of adiposity and other metabolic disorders. Presently, only limited evidence exists describing the molecular alterations leading to impaired brown adipogenesis with aging and the contribution of these processes to changes of systemic energy metabolism. Methods: Samples of young and aged murine brown and white adipose tissue were used to compare age-related changes of brown adipogenic gene expression and thermogenesis-related lipid mobilization. To identify potential markers of brown adipose tissue aging, non-targeted proteomic and metabolomic as well as targeted lipid analyses were conducted on young and aged tissue samples. Subsequently, the effects of several candidate lipid classes on brown adipocyte function were examined. Results: Corroborating previous reports of reduced expression of uncoupling protein-1, we observe impaired signaling required for lipid mobilization in aged brown fat after adrenergic stimulation. Omics analyses additionally confirm the age-related impairment of lipid homeostasis and reveal the accumulation of specific lipid classes, including certain sphingolipids, ceramides, and dolichols in aged brown fat. While ceramides as well as enzymes of dolichol metabolism inhibit brown adipogenesis, inhibition of sphingosine 1-phosphate receptor 2 induces brown adipocyte differentiation. Conclusions: Our functional analyses show that changes in specific lipid species, as observed during aging, may contribute to reduced thermogenic potential. They thus uncover potential biomarkers of aging as well as molecular mechanisms that could contribute to the degradation of brown adipocytes, thereby providing potential treatment strategies of age-related metabolic conditions. KW - Brown adipose tissue KW - Aging KW - Ceramides KW - Sphingolipids KW - Dolichol lipids Y1 - 2019 U6 - https://doi.org/10.1016/j.molmet.2019.03.011 SN - 2212-8778 VL - 24 SP - 1 EP - 17 PB - Elsevier CY - Amsterdam ER - TY - GEN A1 - Pischon, Hannah A1 - Radbruch, Moritz A1 - Ostrowski, Anja A1 - Schumacher, Fabian A1 - Hoenzke, Stefan A1 - Kleuser, Burkhard A1 - Hedtrich, Sarah A1 - Fluhr, Joachim W. A1 - Gruber, Achim D. A1 - Mundhenk, Lars T1 - How Effective Is Tacrolimus in the Imiquimod BT - Induced Mouse Model of Psoriasis? T2 - The journal of investigative dermatology Y1 - 2017 U6 - https://doi.org/10.1016/j.jid.2017.09.019 SN - 0022-202X SN - 1523-1747 VL - 138 IS - 2 SP - 455 EP - 458 PB - Elsevier CY - New York ER - TY - JOUR A1 - Schumacher, Fabian A1 - Chakraborty, Sudipta A1 - Kleuser, Burkhard A1 - Gulbins, Erich A1 - Schwerdtle, Tanja A1 - Aschner, Michael A. A1 - Bornhorst, Julia T1 - Highly sensitive isotope-dilution liquid-chromatography-electrospray ionization-tandem-mass spectrometry approach to study the drug-mediated modulation of dopamine and serotonin levels in Caenorhabditis elegans JF - Talanta : the international journal of pure and applied analytical chemistry N2 - Dopamine (DA) and serotonin (SRT) are monoamine neurotransmitters that play a key role in regulating the central and peripheral nervous system. Their impaired metabolism has been implicated in several neurological disorders, such as Parkinson's disease and depression. Consequently, it is imperative to monitor changes in levels of these low-abundant neurotransmitters and their role in mediating disease. For the first time, a rapid, specific and sensitive isotope-dilution liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and validated for the quantification of DA and SRT in the nematode Caenorhabditis elegans (C. elegans). This model organism offers a unique approach for studying the effect of various drugs and environmental conditions on neurotransmitter levels, given by the conserved DA and SRT biology, including synaptic release, trafficking and formation. We introduce a novel sample preparation protocol incorporating the usage of sodium thiosulfate in perchloric acid as extraction medium that assures high recovery of the relatively unstable neurotransmitters monitored. Moreover, the use of both deuterated internal standards and the multiple reaction monitoring (MRM) technique allows for unequivocal quantification. Thereby, to the best of our knowledge, we achieve a detection sensitivity that clearly exceeds those of published DA and SRT quantification methods in various matrices. We are the first to show that exposure of C elegans to the monoamine oxidase B (MAOB) inhibitor selegiline or the catechol-O-methyltransferase (COMT) inhibitor tolcapone, in order to block DA and SRT degradation, resulted in accumulation of the respective neurotransmitter. Assessment of a behavioral output of the dopaminergic system (basal slowing response) corroborated the analytical LC-MS/MS data. Thus, utilization of the C elegans model system in conjunction with our analytical method is well-suited to investigate drug-mediated modulation of the DA and SRT system in order to identify compounds with neuroprotective or regenerative properties. (C) 2015 Elsevier B.V. All rights reserved. KW - Caenorhabditis elegans KW - Dopamine KW - Serotonin KW - Liquid chromatography-tandem mass spectrometry KW - Isotope-dilution analysis Y1 - 2015 U6 - https://doi.org/10.1016/j.talanta.2015.05.057 SN - 0039-9140 SN - 1873-3573 VL - 144 SP - 71 EP - 79 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Balzus, Benjamin A1 - Sahle, Fitsum Feleke A1 - Hönzke, Stefan A1 - Gerecke, Christian A1 - Schumacher, Fabian A1 - Hedtrich, Sarah A1 - Kleuser, Burkhard A1 - Bodmeier, Roland T1 - Formulation and ex vivo evaluation of polymeric nanoparticles for controlled delivery of corticosteroids to the skin and the corneal epithelium JF - European journal of pharmaceutics and biopharmaceutics : EJPB ; official journal of the International Association for Pharmaceutical Technology N2 - Controlled delivery of corticosteroids using nanoparticles to the skin and corneal epithelium may reduce their side effects and maximize treatment effectiveness. Dexamethasone-loaded ethyl cellulose, Eudragit® RS and ethyl cellulose/Eudragit® RS nanoparticles were prepared by the solvent evaporation method. Dexamethasone release from the polymeric nanoparticles was investigated in vitro using Franz diffusion cells. Drug penetration was also assessed ex vivo using excised human skin. Nanoparticle toxicity was determined by MTT and H2DCFDA assays. Eudragit® RS nanoparticles were smaller and positively charged but had a lower dexamethasone loading capacity (0.3–0.7%) than ethyl cellulose nanoparticles (1.4–2.2%). By blending the two polymers (1:1), small (105 nm), positively charged (+37 mV) nanoparticles with sufficient dexamethasone loading (1.3%) were obtained. Dexamethasone release and penetration significantly decreased with decreasing drug to polymer ratio and increased when Eudragit® RS was blended with ethyl cellulose. Ex vivo, drug release and penetration from the nanoparticles was slower than a conventional cream. The nanoparticles bear no toxicity potentials except ethyl cellulose nanoparticles had ROS generation potential at high concentration. In conclusion, the nanoparticles showed great potential to control the release and penetration of corticosteroids on the skin and mucus membrane and maximize treatment effectiveness. KW - Dermal delivery KW - Dexamethasone KW - Ethyl cellulose KW - Eudragit (R) RS KW - Ocular delivery KW - Polymeric nanoparticle Y1 - 2017 U6 - https://doi.org/10.1016/j.ejpb.2017.02.001 SN - 0939-6411 SN - 1873-3441 VL - 115 SP - 122 EP - 130 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Hausmann, Christian A1 - Zoschke, Christian A1 - Wolff, Christopher A1 - Darvin, Maxim E. A1 - Sochorova, Michaela A1 - Kovacik, Andrej A1 - Wanjiku, Barbara A1 - Schumacher, Fabian A1 - Tigges, Julia A1 - Kleuser, Burkhard A1 - Lademann, Juergen A1 - Fritsche, Ellen A1 - Vavrova, Katerina A1 - Ma, Nan A1 - Schaefer-Korting, Monika T1 - Fibroblast origin shapes tissue homeostasis, epidermal differentiation, and drug uptake JF - Scientific reports N2 - Preclinical studies frequently lack predictive value for human conditions. Human cell-based disease models that reflect patient heterogeneity may reduce the high failure rates of preclinical research. Herein, we investigated the impact of primary cell age and body region on skin homeostasis, epidermal differentiation, and drug uptake. Fibroblasts derived from the breast skin of female 20- to 30-yearolds or 60- to 70-year-olds and fibroblasts from juvenile foreskin (<10 years old) were compared in cell monolayers and in reconstructed human skin (RHS). RHS containing aged fibroblasts differed from its juvenile and adult counterparts, especially in terms of the dermal extracellular matrix composition and interleukin-6 levels. The site from which the fibroblasts were derived appeared to alter fibroblast-keratinocyte crosstalk by affecting, among other things, the levels of granulocyte-macrophage colony-stimulating factor. Consequently, the epidermal expression of filaggrin and e-cadherin was increased in RHS containing breast skin fibroblasts, as were lipid levels in the stratum corneum. In conclusion, the region of the body from which fibroblasts are derived appears to affect the epidermal differentiation of RHS, while the age of the fibroblast donors determines the expression of proteins involved in wound healing. Emulating patient heterogeneity in preclinical studies might improve the treatment of age-related skin conditions. Y1 - 2019 U6 - https://doi.org/10.1038/s41598-019-39770-6 SN - 2045-2322 VL - 9 PB - Nature Publ. Group CY - London ER - TY - GEN A1 - Doege, N. A1 - Hoenzke, S. A1 - Schumacher, Fabian A1 - Balzus, Benjamin A1 - Colombo, Miriam A1 - Hadam, S. A1 - Rancan, F. A1 - Blume-Peytavi, Ulrike A1 - Schindler, A. A1 - Ruehl, E. A1 - Skov, P. A1 - Church, Martin K. A1 - Hedtrich, Sarah A1 - Kleuser, Burkhard A1 - Bodmeier, Roland A1 - Vogt, A. T1 - Ex vivo microdialysis used for the preclinical assessment of anti-inflammatory therapy T2 - Experimental dermatology : the official journal of the European Immunodermatology Society Y1 - 2016 SN - 0906-6705 SN - 1600-0625 VL - 25 SP - E32 EP - E32 PB - Wiley-Blackwell CY - Hoboken ER - TY - JOUR A1 - Döge, Nadine A1 - Hönzke, Stefan A1 - Schumacher, Fabian A1 - Balzus, Benjamin A1 - Colombo, Miriam A1 - Hadam, Sabrina A1 - Rancan, Fiorenza A1 - Blume-Peytavi, Ulrike A1 - Schäfer-Korting, Monika A1 - Schindler, Anke A1 - Rühl, Eckart A1 - Skov, Per Stahl A1 - Church, Martin K. A1 - Hedtrich, Sarah A1 - Kleuser, Burkhard A1 - Bodmeier, Roland A1 - Vogt, Annika T1 - Ethyl cellulose nanocarriers and nanocrystals differentially deliver dexamethasone into intact, tape-stripped or sodium lauryl sulfate-exposed ex vivo human skin - assessment by intradermal microdialysis and extraction from the different skin layers JF - Journal of controlled release N2 - Understanding penetration not only in intact, but also in lesional skin with impaired skin barrier function is important, in order to explore the surplus value of nanoparticle-based drug delivery for anti-inflammatory dermatotherapy. Herein, short-termex vivo cultures of (i) intact human skin, (ii) skin pretreated with tape-strippings and (iii) skin pre-exposed to sodium lauryl sulfate (SLS) were used to assess the penetration of dexamethasone (Dex). Intradermal microdialysis was utilized for up to 24 h after drug application as commercial cream, nanocrystals or ethyl cellulose nanocarriers applied at the therapeutic concentration of 0.05%, respectively. In addition, Dex was assessed in culture media and extracts from stratum corneum, epidermis and dermis after 24 h, and the results were compared to those in heat-separated split skin from studies in Franz diffusion cells. Providing fast drug release, nanocrystals significantly accelerated the penetration of Dex. In contrast to the application of cream and ethyl cellulose nanocarriers, Dex was already detectable in eluates after 6 h when applying nanocrystals on intact skin. Disruption of the skin barrier further accelerated and enhanced the penetration. Encapsulation in ethyl cellulose nanocarriers delayed Dex penetration. Interestingly, for all formulations highly increased concentrations in the dialysate were observed in tape-stripped skin, whereas the extent of enhancement was less in SLS-exposed skin. The results were confirmed in tissue extracts and were in line with the predictions made by in vitro release studies and ex vivo Franz diffusion cell experiments. The use of 45 kDa probes further enabled the collection of inflammatory cytokines. However, the estimation of glucocorticoid efficacy by Interleukin (IL)-6 and IL-8 analysis was limited due to the trauma induced by the probe insertion. Ex vivo intradermal microdialysis combined with culture media analysis provides an effective, skin-sparing method for preclinical assessment of novel drug delivery systems at therapeutic doses in models of diseased skin. (C) 2016 Elsevier B.V. All rights reserved. KW - Drug delivery systems KW - Polymeric nanoparticles KW - Dexamethasone KW - Microdialysis KW - Skin penetration KW - Skin barrier disruption Y1 - 2016 U6 - https://doi.org/10.1016/j.jconrel.2016.07.009 SN - 0168-3659 SN - 1873-4995 VL - 242 SP - 25 EP - 34 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Wetzel, Alexandra Nicole A1 - Scholtka, Bettina A1 - Schumacher, Fabian A1 - Rawel, Harshadrai Manilal A1 - Geisendörfer, Birte A1 - Kleuser, Burkhard T1 - Epigenetic DNA methylation of EBI3 modulates human interleukin-35 formation via NFkB signaling BT - a promising therapeutic option in ulcerative colitis JF - International journal of molecular sciences N2 - Ulcerative colitis (UC), a severe chronic disease with unclear etiology that is associated with increased risk for colorectal cancer, is accompanied by dysregulation of cytokines. Epstein-Barr virus-induced gene 3 (EBI3) encodes a subunit in the unique heterodimeric IL-12 cytokine family of either pro- or anti-inflammatory function. After having recently demonstrated that upregulation of EBI3 by histone acetylation alleviates disease symptoms in a dextran sulfate sodium (DSS)-treated mouse model of chronic colitis, we now aimed to examine a possible further epigenetic regulation of EBI3 by DNA methylation under inflammatory conditions. Treatment with the DNA methyltransferase inhibitor (DNMTi) decitabine (DAC) and TNF alpha led to synergistic upregulation of EBI3 in human colon epithelial cells (HCEC). Use of different signaling pathway inhibitors indicated NF kappa B signaling was necessary and proportional to the synergistic EBI3 induction. MALDI-TOF/MS and HPLC-ESIMS/MS analysis of DAC/TNF alpha-treated HCEC identified IL-12p35 as the most probable binding partner to form a functional protein. EBI3/IL-12p35 heterodimers (IL-35) induce their own gene upregulation, something that was indeed observed in HCEC cultured with media from previously DAC/TNF alpha-treated HCEC. These results suggest that under inflammatory and demethylating conditions the upregulation of EBI3 results in the formation of anti-inflammatory IL-35, which might be considered as a therapeutic target in colitis. KW - decitabine KW - DNMT inhibitor KW - EBI3 KW - inhibitory cytokines KW - interleukin-35 KW - TNF alpha KW - Ulcerative colitis Y1 - 2021 U6 - https://doi.org/10.3390/ijms22105329 SN - 1422-0067 VL - 22 IS - 10 PB - MDPI CY - Basel ER - TY - JOUR A1 - Giulbudagian, Michael A1 - Hönzke, Stefan A1 - Bergueiro, Julián A1 - Işık, Doğuş A1 - Schumacher, Fabian A1 - Saeidpour, Siavash A1 - Lohan, Silke A1 - Meinke, Martina A1 - Teutloff, Christian A1 - Schäfer-Korting, Monika A1 - Yealland, Guy A1 - Kleuser, Burkhard A1 - Hedtrich, Sarah A1 - Calderón, Marcelo T1 - Enhanced topical delivery of dexamethasone by beta-cyclodextrin decorated thermoresponsive nanogels JF - Nanoscale N2 - Highly hydrophilic, responsive nanogels are attractive as potential systems for the topical delivery of bioactives encapsulated in their three-dimensional polymeric scaffold. Yet, these drug carrier systems suffer from drawbacks for efficient delivery of hydrophobic drugs. Addressing this, β-cyclodextrin (βCD) could be successfully introduced into the drug carrier systems by exploiting its unique affinity toward dexamethasone (DXM) as well as its role as topical penetration enhancer. The properties of βCD could be combined with those of thermoresponsive nanogels (tNGs) based on dendritic polyglycerol (dPG) as a crosslinker and linear thermoresponsive polyglycerol (tPG) inducing responsiveness to temperature changes. Electron paramagnetic resonance (EPR) studies localized the drug within the hydrophobic cavity of βCD by differences in its mobility and environmental polarity. In fact, the fabricated carriers combining a particulate delivery system with a conventional penetration enhancer, resulted in an efficient delivery of DXM to the epidermis and the dermis of human skin ex vivo (enhancement compared to commercial DXM cream: ∼2.5 fold in epidermis, ∼30 fold in dermis). Furthermore, DXM encapsulated in βCD tNGs applied to skin equivalents downregulated the expression of proinflammatory thymic stromal lymphopoietin (TSLP) and outperformed a commercially available DXM cream. Y1 - 2017 U6 - https://doi.org/10.1039/c7nr04480a SN - 2040-3364 SN - 2040-3372 VL - 10 IS - 1 SP - 469 EP - 479 PB - Royal Society of Chemistry CY - Cambridge ER - TY - JOUR A1 - Kachler, Katerina A1 - Bailer, Maximilian A1 - Heim, Lisanne A1 - Schumacher, Fabian A1 - Reichel, Martin A1 - Holzinger, Corinna D. A1 - Trump, Sonja A1 - Mittler, Susanne A1 - Monti, Juliana A1 - Trufa, Denis I. A1 - Rieker, Ralf J. A1 - Hartmann, Arndt A1 - Sirbu, Horia A1 - Kleuser, Burkhard A1 - Kornhuber, Johannes A1 - Finotto, Susetta T1 - Enhanced acid sphingomyelinase activity drives immune evasion and tumor growth in non-small cell lung carcinoma JF - Cancer research N2 - The lipid hydrolase enzyme acid sphingomyelinase (ASM) is required for the conversion of the lipid cell membrane component sphingomyelin into ceramide. In cancer cells, ASM-mediated ceramide production is important for apoptosis, cell proliferation, and immune modulation, highlighting ASM as a potential multimodal therapeutic target. In this study, we demonstrate elevated ASM activity in the lung tumor environment and blood serum of patients with non-small cell lung cancer (NSCLC). RNAi-mediated attenuation of SMPD1 in human NSCLC cells rendered them resistant to serum starvation-induced apoptosis. In a murine model of lung adenocarcinoma, ASM deficiency reduced tumor development in a manner associated with significant enhancement of Th1-mediated and cytotoxic T-cell-mediated antitumor immunity. Our findings indicate that targeting ASM in NSCLC can act by tumor cell-intrinsic and-extrinsic mechanisms to suppress tumor cell growth, most notably by enabling an effective antitumor immune response by the host. (C) 2017 AACR. Y1 - 2017 U6 - https://doi.org/10.1158/0008-5472.CAN-16-3313 SN - 0008-5472 SN - 1538-7445 VL - 77 IS - 21 SP - 5963 EP - 5976 PB - American Association for Cancer Research CY - Philadelphia ER - TY - JOUR A1 - Schoenauer, Roman A1 - Larpin, Yu A1 - Babiychuk, Eduard B. A1 - Drucker, Patrick A1 - Babiychuk, Viktoriia S. A1 - Avota, Elita A1 - Schneider-Schaulies, Sibylle A1 - Schumacher, Fabian A1 - Kleuser, Burkhard A1 - Koffel, Rene A1 - Draeger, Annette T1 - Down-regulation of acid sphingomyelinase and neutral sphingomyelinase-2 inversely determines the cellular resistance to plasmalemmal injury by pore-forming toxins JF - The FASEB journal : the official journal of the Federation of American Societies for Experimental Biology N2 - Bacterial pore-forming toxins compromise plasmalemmal integrity, leading to Ca2+ influx, leakage of the cytoplasm, and cell death. Such lesions can be repaired by microvesicular shedding or by the endocytic uptake of the injured membrane sites. Cells have at their disposal an entire toolbox of repair proteins for the identification and elimination of membrane lesions. Sphingomyelinases catalyze the breakdown of sphingomyelin into ceramide and phosphocholine. Sphingomyelin is predominantly localized in the outer leaflet, where it is hydrolyzed by acid sphingomyelinase (ASM) after lysosomal fusion with the plasma membrane. The magnesium-dependent neutral sphingomyelinase (NSM)-2 is found at the inner leaflet of the plasmalemma. Because either sphingomyelinase has been ascribed a role in the cellular stress response, we investigated their role in plasma membrane repair and cellular survival after treatment with the pore-forming toxins listeriolysin O (LLO) or pneumolysin (PLY). Jurkat T cells, in which ASM or NSM-2 was down-regulated [ASM knockdown (KD) or NSM-2 KD cells], showed inverse reactions to toxin-induced membrane damage: ASM KD cells displayed reduced toxin resistance, decreased viability, and defects in membrane repair. In contrast, the down-regulation of NSM-2 led to an increase in viability and enhanced plasmalemmal repair. Yet, in addition to the increased plasmalemmal repair, the enhanced toxin resistance of NSM-2 KD cells also appeared to be dependent on the activation of p38/MAPK, which was constitutively activated, whereas in ASM KD cells, the p38/MAPK activation was constitutively blunted.Schoenauer, R., Larpin, Y., Babiychuk, E. B., Drucker, P., Babiychuk, V. S., Avota, E., Schneider-Schaulies, S., Schumacher, F., Kleuser, B., Koffel, R., Draeger, A. Down-regulation of acid sphingomyelinase and neutral sphingomyelinase-2 inversely determines the cellular resistance to plasmalemmal injury by pore-forming toxins. KW - membrane repair KW - blebbing KW - calcium KW - bacterial toxins KW - annexins Y1 - 2018 U6 - https://doi.org/10.1096/fj.201800033R SN - 0892-6638 SN - 1530-6860 VL - 33 IS - 1 SP - 275 EP - 285 PB - Federation of American Societies for Experimental Biology CY - Bethesda ER - TY - GEN A1 - Rancan, Fiorenza A1 - Volkmann, Hildburg A1 - Giulbudagian, Michael A1 - Schumacher, Fabian A1 - Stanko, Jessica Isolde A1 - Kleuser, Burkhard A1 - Blume-Peytavi, Ulrike A1 - Calderón, Marcelo A1 - Vogt, Annika T1 - Dermal Delivery of the High-Molecular-Weight Drug Tacrolimus by Means of Polyglycerol-Based Nanogels T2 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe N2 - Polyglycerol-based thermoresponsive nanogels (tNGs) have been shown to have excellent skin hydration properties and to be valuable delivery systems for sustained release of drugs into skin. In this study, we compared the skin penetration of tacrolimus formulated in tNGs with a commercial 0.1% tacrolimus ointment. The penetration of the drug was investigated in ex vivo abdominal and breast skin, while different methods for skin barrier disruption were investigated to improve skin permeability or simulate inflammatory conditions with compromised skin barrier. The amount of penetrated tacrolimus was measured in skin extracts by liquid chromatography tandem-mass spectrometry (LC-MS/MS), whereas the inflammatory markers IL-6 and IL-8 were detected by enzyme-linked immunosorbent assay (ELISA). Higher amounts of tacrolimus penetrated in breast as compared to abdominal skin or in barrier-disrupted as compared to intact skin, confirming that the stratum corneum is the main barrier for tacrolimus skin penetration. The anti-proliferative effect of the penetrated drug was measured in skin tissue/Jurkat cells co-cultures. Interestingly, tNGs exhibited similar anti-proliferative effects as the 0.1% tacrolimus ointment. We conclude that polyglycerol-based nanogels represent an interesting alternative to paraffin-based formulations for the treatment of inflammatory skin conditions. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 1339 KW - tacrolimus formulation KW - nanogels KW - skin penetration KW - drug delivery KW - human excised skin KW - Jurkat cells Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-473270 SN - 1866-8372 IS - 1339 ER - TY - JOUR A1 - Rancan, Fiorenza A1 - Volkmann, Hildburg A1 - Giulbudagian, Michael A1 - Schumacher, Fabian A1 - Stanko, Jessica Isolde A1 - Kleuser, Burkhard A1 - Blume-Peytavi, Ulrike A1 - Calderon, Marcelo A1 - Vogt, Annika T1 - Dermal Delivery of the High-Molecular-Weight Drug Tacrolimus by Means of Polyglycerol-Based Nanogels JF - Pharmaceutics : Molecular Diversity Preservation International N2 - Polyglycerol-based thermoresponsive nanogels (tNGs) have been shown to have excellent skin hydration properties and to be valuable delivery systems for sustained release of drugs into skin. In this study, we compared the skin penetration of tacrolimus formulated in tNGs with a commercial 0.1% tacrolimus ointment. The penetration of the drug was investigated in ex vivo abdominal and breast skin, while different methods for skin barrier disruption were investigated to improve skin permeability or simulate inflammatory conditions with compromised skin barrier. The amount of penetrated tacrolimus was measured in skin extracts by liquid chromatography tandem-mass spectrometry (LC-MS/MS), whereas the inflammatory markers IL-6 and IL-8 were detected by enzyme-linked immunosorbent assay (ELISA). Higher amounts of tacrolimus penetrated in breast as compared to abdominal skin or in barrier-disrupted as compared to intact skin, confirming that the stratum corneum is the main barrier for tacrolimus skin penetration. The anti-proliferative effect of the penetrated drug was measured in skin tissue/Jurkat cells co-cultures. Interestingly, tNGs exhibited similar anti-proliferative effects as the 0.1% tacrolimus ointment. We conclude that polyglycerol-based nanogels represent an interesting alternative to paraffin-based formulations for the treatment of inflammatory skin conditions. KW - tacrolimus formulation KW - nanogels KW - skin penetration KW - drug delivery KW - human excised skin KW - Jurkat cells Y1 - 2019 U6 - https://doi.org/10.3390/pharmaceutics11080394 SN - 1999-4923 VL - 11 IS - 8 PB - MDPI CY - Basel ER - TY - JOUR A1 - Frombach, Janna A1 - Unbehauen, Michael A1 - Kurniasih, Indah N. A1 - Schumacher, Fabian A1 - Volz, Pierre A1 - Hadam, Sabrina A1 - Rancan, Fiorenza A1 - Blume-Peytavi, Ulrike A1 - Kleuser, Burkhard A1 - Haag, Rainer A1 - Alexiev, Ulrike A1 - Vogt, Annika T1 - Core-multishell nanocarriers enhance drug penetration and reach keratinocytes and antigen-presenting cells in intact human skin JF - Journal of controlled release N2 - In reconstructed skin and diffusion cell studies, core-multishell nanocarriers (CMS-NC) showed great potential for drug delivery across the skin barrier. Herein, we investigated penetration, release of dexamethasone (DXM), in excised full-thickness human skin with special focus on hair follicles (HF). Four hours and 16 h after topical application of clinically relevant dosages of 10 mu g DXM/cm(2) skin encapsulated in CMS-NC (12 nm diameter, 5.8% loading), presence of DXM in the tissue as assessed by fluorescence microscopy of anti-DXM-stained tissue sections as well as ELISA and HPLC-MS/MS in tissue extracts was enhanced compared to standard LAW-creme but lower compared to DXM aqueous/alcoholic solution. Such enhanced penetration compared to conventional cremes offers high potential for topical therapies, as recurrent applications of corticosteroid solutions face limitations with regard to tolerability and fast drainage. The findings encourage more detailed investigations on where and how the nanocarrier and drug dissociate within the skin and what other factors, e.g. thermodynamic activity, influence the penetration of this formulations. Microscopic studies on the spatial distribution within the skin revealed accumulation in HF and furrows accompanied by limited cellular uptake assessed by flow cytometry (up to 9% of total epidermal cells). FLIM clearly visualized the presence of CMS-NC in the viable epidermis and dermis. When exposed in situ a fraction of up to 25% CD1a(+) cells were found within the epidermal CMS-NC+ population compared to approximately 3% CD1a(+)/CMS-NC+ cells after in vitro exposure in short-term cultures of epidermal cell suspensions. The latter reflects the natural percentage of Langerhans cells (LC) in epidermis suspensions and indicated that CMS-NC were not preferentially internalized by one cell type. The increased CMS-NC+ LC proportion after exposure within the tissue is in accordance with the strategic suprabasal LC-localization. More specifically we postulate that the extensive dendrite meshwork, their position around HF orifices and their capacity to modulate tight junctions facilitated a preferential uptake of CMS-NC by LC within the skin. This newly identified aspect of CMS-NC penetration underlines the potential of CMS-NC for dermatotherapy and encourages further investigations of CMS-NC for the delivery of other molecule classes for which intracellular delivery is even more crucial. KW - Drug delivery KW - Skin penetration KW - Cellular uptake KW - Nanoparticles KW - Dendritic cells KW - High resolution microscopy Y1 - 2019 U6 - https://doi.org/10.1016/j.jconrel.2019.02.028 SN - 0168-3659 SN - 1873-4995 VL - 299 SP - 138 EP - 148 PB - Elsevier CY - Amsterdam ER - TY - GEN A1 - Naser, Eyad A1 - Kadow, Stephanie A1 - Schumacher, Fabian A1 - Mohamed, Zainelabdeen H. A1 - Kappe, Christian A1 - Hessler, Gabriele A1 - Pollmeier, Barbara A1 - Kleuser, Burkhard A1 - Arenz, Christoph A1 - Becker, Katrin Anne A1 - Gulbins, Erich A1 - Carpinteiro, Alexander T1 - Characterization of the small molecule ARC39 BT - a direct and specific inhibitor of acid sphingomyelinase in vitro[S] T2 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe N2 - Inhibition of acid sphingomyelinase (ASM), a lysosomal enzyme that catalyzes the hydrolysis of sphingomyelin into ceramide and phosphorylcholine, may serve as an investigational tool or a therapeutic intervention to control many diseases. Specific ASM inhibitors are currently not sufficiently characterized. Here, we found that 1-aminodecylidene bis-phosphonic acid (ARC39) specifically and efficiently (>90%) inhibits both lysosomal and secretory ASM in vitro. Results from investigating sphingomyelin phosphodiesterase 1 (SMPD1/Smpd1) mRNA and ASM protein levels suggested that ARC39 directly inhibits ASM's catalytic activity in cultured cells, a mechanism that differs from that of functional inhibitors of ASM. We further provide evidence that ARC39 dose- and time-dependently inhibits lysosomal ASM in intact cells, and we show that ARC39 also reduces platelet- and ASM-promoted adhesion of tumor cells. The observed toxicity of ARC39 is low at concentrations relevant for ASM inhibition in vitro, and it does not strongly alter the lysosomal compartment or induce phospholipidosis in vitro. When applied intraperitoneally in vivo, even subtoxic high doses administered short-term induced sphingomyelin accumulation only locally in the peritoneal lavage without significant accumulation in plasma, liver, spleen, or brain. These findings require further investigation with other possible chemical modifications. In conclusion, our results indicate that ARC39 potently and selectively inhibits ASM in vitro and highlight the need for developing compounds that can reach tissue concentrations sufficient for ASM inhibition in vivo. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 1407 KW - sphingolipids KW - sphingomyelin KW - cerami-des KW - lipid metabolism KW - enzymology KW - lysosome KW - lysosomal hydrolases KW - acid ceramidase KW - bisphosphonates KW - functional inhibitors of acid sphin-gomyelinase KW - 1-aminodecylidene bis-phosphonic acid Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-516635 SN - 1866-8372 IS - 6 ER - TY - JOUR A1 - Naser, Eyad A1 - Kadow, Stephanie A1 - Schumacher, Fabian A1 - Mohamed, Zainelabdeen H. A1 - Kappe, Christian A1 - Hessler, Gabriele A1 - Pollmeier, Barbara A1 - Kleuser, Burkhard A1 - Arenz, Christoph A1 - Becker, Katrin Anne A1 - Gulbins, Erich A1 - Carpinteiro, Alexander T1 - Characterization of the small molecule ARC39 BT - a direct and specific inhibitor of acid sphingomyelinase in vitro[S] JF - Journal of Lipid Research N2 - Inhibition of acid sphingomyelinase (ASM), a lysosomal enzyme that catalyzes the hydrolysis of sphingomyelin into ceramide and phosphorylcholine, may serve as an investigational tool or a therapeutic intervention to control many diseases. Specific ASM inhibitors are currently not sufficiently characterized. Here, we found that 1-aminodecylidene bis-phosphonic acid (ARC39) specifically and efficiently (>90%) inhibits both lysosomal and secretory ASM in vitro. Results from investigating sphingomyelin phosphodiesterase 1 (SMPD1/Smpd1) mRNA and ASM protein levels suggested that ARC39 directly inhibits ASM's catalytic activity in cultured cells, a mechanism that differs from that of functional inhibitors of ASM. We further provide evidence that ARC39 dose- and time-dependently inhibits lysosomal ASM in intact cells, and we show that ARC39 also reduces platelet- and ASM-promoted adhesion of tumor cells. The observed toxicity of ARC39 is low at concentrations relevant for ASM inhibition in vitro, and it does not strongly alter the lysosomal compartment or induce phospholipidosis in vitro. When applied intraperitoneally in vivo, even subtoxic high doses administered short-term induced sphingomyelin accumulation only locally in the peritoneal lavage without significant accumulation in plasma, liver, spleen, or brain. These findings require further investigation with other possible chemical modifications. In conclusion, our results indicate that ARC39 potently and selectively inhibits ASM in vitro and highlight the need for developing compounds that can reach tissue concentrations sufficient for ASM inhibition in vivo. KW - sphingolipids KW - sphingomyelin KW - cerami-des KW - lipid metabolism KW - enzymology KW - lysosome KW - lysosomal hydrolases KW - acid ceramidase KW - bisphosphonates KW - functional inhibitors of acid sphin-gomyelinase KW - 1-aminodecylidene bis-phosphonic acid Y1 - 2021 U6 - https://doi.org/10.1194/jlr.RA120000682 SN - 1539-7262 SN - 0022-2275 VL - 61 IS - 6 SP - 896 EP - 910 PB - American Society for Biochemistry and Molecular Biology CY - Bethesda ER - TY - GEN A1 - Wardelmann, Kristina A1 - Rath, Michaela A1 - Castro, José Pedro A1 - Blümel, Sabine A1 - Schell, Mareike A1 - Hauffe, Robert A1 - Schumacher, Fabian A1 - Flore, Tanina A1 - Ritter, Katrin A1 - Wernitz, Andreas A1 - Hosoi, Toru A1 - Ozawa, Koichiro A1 - Kleuser, Burkhard A1 - Weiß, Jürgen A1 - Schürmann, Annette A1 - Kleinridders, André T1 - Central acting Hsp10 regulates mitochondrial function, fatty acid metabolism and insulin sensitivity in the hypothalamus T2 - Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe N2 - Mitochondria are critical for hypothalamic function and regulators of metabolism. Hypothalamic mitochondrial dysfunction with decreased mitochondrial chaperone expression is present in type 2 diabetes (T2D). Recently, we demonstrated that a dysregulated mitochondrial stress response (MSR) with reduced chaperone expression in the hypothalamus is an early event in obesity development due to insufficient insulin signaling. Although insulin activates this response and improves metabolism, the metabolic impact of one of its members, the mitochondrial chaperone heat shock protein 10 (Hsp10), is unknown. Thus, we hypothesized that a reduction of Hsp10 in hypothalamic neurons will impair mitochondrial function and impact brain insulin action. Therefore, we investigated the role of chaperone Hsp10 by introducing a lentiviral-mediated Hsp10 knockdown (KD) in the hypothalamic cell line CLU-183 and in the arcuate nucleus (ARC) of C57BL/6N male mice. We analyzed mitochondrial function and insulin signaling utilizing qPCR, Western blot, XF96 Analyzer, immunohistochemistry, and microscopy techniques. We show that Hsp10 expression is reduced in T2D mice brains and regulated by leptin in vitro. Hsp10 KD in hypothalamic cells induced mitochondrial dysfunction with altered fatty acid metabolism and increased mitochondria-specific oxidative stress resulting in neuronal insulin resistance. Consequently, the reduction of Hsp10 in the ARC of C57BL/6N mice caused hypothalamic insulin resistance with acute liver insulin resistance. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 1165 KW - brain insulin signaling KW - mitochondria KW - oxidative stress KW - fatty acid metabolism Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-522985 SN - 1866-8372 IS - 5 ER - TY - JOUR A1 - Wardelmann, Kristina A1 - Rath, Michaela A1 - Castro, José Pedro A1 - Blümel, Sabine A1 - Schell, Mareike A1 - Hauffe, Robert A1 - Schumacher, Fabian A1 - Flore, Tanina A1 - Ritter, Katrin A1 - Wernitz, Andreas A1 - Hosoi, Toru A1 - Ozawa, Koichiro A1 - Kleuser, Burkhard A1 - Weiß, Jürgen A1 - Schürmann, Annette A1 - Kleinridders, André T1 - Central acting Hsp10 regulates mitochondrial function, fatty acid metabolism and insulin sensitivity in the hypothalamus JF - Antioxidants N2 - Mitochondria are critical for hypothalamic function and regulators of metabolism. Hypothalamic mitochondrial dysfunction with decreased mitochondrial chaperone expression is present in type 2 diabetes (T2D). Recently, we demonstrated that a dysregulated mitochondrial stress response (MSR) with reduced chaperone expression in the hypothalamus is an early event in obesity development due to insufficient insulin signaling. Although insulin activates this response and improves metabolism, the metabolic impact of one of its members, the mitochondrial chaperone heat shock protein 10 (Hsp10), is unknown. Thus, we hypothesized that a reduction of Hsp10 in hypothalamic neurons will impair mitochondrial function and impact brain insulin action. Therefore, we investigated the role of chaperone Hsp10 by introducing a lentiviral-mediated Hsp10 knockdown (KD) in the hypothalamic cell line CLU-183 and in the arcuate nucleus (ARC) of C57BL/6N male mice. We analyzed mitochondrial function and insulin signaling utilizing qPCR, Western blot, XF96 Analyzer, immunohistochemistry, and microscopy techniques. We show that Hsp10 expression is reduced in T2D mice brains and regulated by leptin in vitro. Hsp10 KD in hypothalamic cells induced mitochondrial dysfunction with altered fatty acid metabolism and increased mitochondria-specific oxidative stress resulting in neuronal insulin resistance. Consequently, the reduction of Hsp10 in the ARC of C57BL/6N mice caused hypothalamic insulin resistance with acute liver insulin resistance. KW - brain insulin signaling KW - mitochondria KW - oxidative stress KW - fatty acid metabolism Y1 - 2021 U6 - https://doi.org/10.3390/antiox10050711 SN - 2076-3921 VL - 10 IS - 5 PB - MDPI CY - Basel ER - TY - JOUR A1 - Beckmann, Nadine A1 - Schumacher, Fabian A1 - Kleuser, Burkhard A1 - Gulbins, Erich A1 - Nomellini, Vanessa A1 - Caldwell, Charles C. T1 - Burn injury impairs neutrophil chemotaxis through increased ceramide JF - Shock : injury, inflammation, and sepsis, laboratory and clinical approaches N2 - Infection is a common and often deadly complication after burn injury. A major underlying factor is burn-induced immune dysfunction, particularly with respect to neutrophils as the primary responders to infection. Temporally after murine scald injury, we demonstrate impaired bone marrow neutrophil chemotaxis toward CXCL1 ex vivo. Additionally, we observed a reduced recruitment of neutrophils to the peritoneal after elicitation 7 days after injury. We demonstrate that neutrophil ceramide levels increase after burn injury, and this is associated with decreased expression of CXCR2 and blunted chemotaxis. A major signaling event upon CXCR2 activation is Akt phosphorylation and this was reduced when ceramide was elevated. In contrast, PTEN levels were elevated and PTEN-inhibition elevated phospho-Akt levels and mitigated the burn-induced neutrophil chemotaxis defect. Altogether, this study identifies a newly described pathway of ceramide-mediated suppression of neutrophil chemotaxis after burn injury and introduces potential targets to mitigate this defect and reduce infection-related morbidity and mortality after burn. KW - Acid sphingomyelinase KW - Akt KW - burn injury KW - ceramide KW - CXCR2 KW - immune KW - dysfunction KW - neutrophil chemotaxis KW - PTEN Y1 - 2021 U6 - https://doi.org/10.1097/SHK.0000000000001693 SN - 1073-2322 SN - 1540-0514 VL - 56 IS - 1 SP - 125 EP - 132 PB - Lippincott Williams & Wilkins CY - Hagerstown, Md. ER - TY - JOUR A1 - Gerecke, Christian A1 - Edlich, Alexander A1 - Giulbudagian, Michael A1 - Schumacher, Fabian A1 - Zhang, Nan A1 - Said, Andre A1 - Yealland, Guy A1 - Lohan, Silke B. A1 - Neumann, Falko A1 - Meinke, Martina C. A1 - Ma, Nan A1 - Calderon, Marcelo A1 - Hedtrich, Sarah A1 - Schaefer-Korting, Monika A1 - Kleuser, Burkhard T1 - Biocompatibility and characterization of polyglycerol-based thermoresponsive nanogels designed as novel drug-delivery systems and their intracellular localization in keratinocytes JF - Nanotoxicology N2 - Novel nanogels that possess the capacity to change their physico-chemical properties in response to external stimuli are promising drug-delivery candidates for the treatment of severe skin diseases. As thermoresponsive nanogels (tNGs) are capable of enhancing penetration through biological barriers such as the stratum corneum and are taken up by keratinocytes of human skin, potential adverse consequences of their exposure must be elucidated. In this study, tNGs were synthesized from dendritic polyglycerol (dPG) and two thermoresponsive polymers. tNG_dPG_tPG are the combination of dPG with poly(glycidyl methyl ether-co-ethyl glycidyl ether) (p(GME-co-EGE)) and tNG_dPG_pNIPAM the one with poly(N-isopropylacrylamide) (pNIPAM). Both thermoresponsive nanogels are able to incorporate high amounts of dexamethasone and tacrolimus, drugs used in the treatment of severe skin diseases. Cellular uptake, intracellular localization and the toxicological properties of the tNGs were comprehensively characterized in primary normal human keratinocytes (NHK) and in spontaneously transformed aneuploid immortal keratinocyte cell line from adult human skin (HaCaT). Laser scanning confocal microscopy revealed fluorescently labeled tNGs entered into the cells and localized predominantly within lysosomal compartments. MTT assay, comet assay and carboxy-H2DCFDA assay, demonstrated neither cytotoxic or genotoxic effects, nor any induction of reactive oxygen species of the tNGs in keratinocytes. In addition, both tNGs were devoid of eye irritation potential as shown by bovine corneal opacity and permeability (BCOP) test and red blood cell (RBC) hemolysis assay. Therefore, our study provides evidence that tNGs are locally well tolerated and underlines their potential for cutaneous drug delivery. KW - Drug delivery KW - nanoparticles KW - particle characterization KW - keratinocytes KW - nanotoxicology Y1 - 2017 U6 - https://doi.org/10.1080/17435390.2017.1292371 SN - 1743-5390 SN - 1743-5404 VL - 11 SP - 267 EP - 277 PB - Routledge, Taylor & Francis Group CY - Abingdon ER - TY - GEN A1 - Gerecke, Christian A1 - Edlich, Alexander A1 - Giulbudagian, Michael A1 - Schumacher, Fabian A1 - Zhang, Nan A1 - Said, Andre A1 - Yealland, Guy A1 - Lohan, Silke B. A1 - Neumann, Falko A1 - Meinke, Martina C. A1 - Ma, Nan A1 - Calderón, Marcelo A1 - Hedtrich, Sarah A1 - Schäfer-Korting, Monika A1 - Kleuser, Burkhard T1 - Biocompatibility and characterization of polyglycerol-based thermoresponsive nanogels designed as novel drug-delivery systems and their intracellular localization in keratinocytes N2 - Novel nanogels that possess the capacity to change their physico-chemical properties in response to external stimuli are promising drug-delivery candidates for the treatment of severe skin diseases. As thermoresponsive nanogels (tNGs) are capable of enhancing penetration through biological barriers such as the stratum corneum and are taken up by keratinocytes of human skin, potential adverse consequences of their exposure must be elucidated. In this study, tNGs were synthesized from dendritic polyglycerol (dPG) and two thermoresponsive polymers. tNG_dPG_tPG are the combination of dPG with poly(glycidyl methyl ether-co-ethyl glycidyl ether) (p(GME-co-EGE)) and tNG_dPG_pNIPAM the one with poly(N-isopropylacrylamide) (pNIPAM). Both thermoresponsive nanogels are able to incorporate high amounts of dexamethasone and tacrolimus, drugs used in the treatment of severe skin diseases. Cellular uptake, intracellular localization and the toxicological properties of the tNGs were comprehensively characterized in primary normal human keratinocytes (NHK) and in spontaneously transformed aneuploid immortal keratinocyte cell line from adult human skin (HaCaT). Laser scanning confocal microscopy revealed fluorescently labeled tNGs entered into the cells and localized predominantly within lysosomal compartments. MTT assay, comet assay and carboxy-H2DCFDA assay, demonstrated neither cytotoxic or genotoxic effects, nor any induction of reactive oxygen species of the tNGs in keratinocytes. In addition, both tNGs were devoid of eye irritation potential as shown by bovine corneal opacity and permeability (BCOP) test and red blood cell (RBC) hemolysis assay. Therefore, our study provides evidence that tNGs are locally well tolerated and underlines their potential for cutaneous drug delivery. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 335 KW - Drug delivery KW - nanoparticles KW - particle characterization KW - keratinocytes KW - nanotoxicology Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-395325 ER - TY - JOUR A1 - Fink, Julian A1 - Schumacher, Fabian A1 - Schlegel, Jan A1 - Stenzel, Philipp A1 - Wigger, Dominik A1 - Sauer, Markus A1 - Kleuser, Burkhard A1 - Seibel, Jürgen T1 - Azidosphinganine enables metabolic labeling and detection of sphingolipid de novo synthesis JF - Organic & biomolecular chemistry : an international journal of synthetic, physical and biomolecular organic chemistry N2 - Here were report the combination of biocompatible click chemistry of omega-azidosphinganine with fluorescence microscopy and mass spectrometry as a powerful tool to elaborate the sphingolipid metabolism. The azide probe was efficiently synthesized over 13 steps starting from l-serine in an overall yield of 20% and was used for live-cell fluorescence imaging of the endoplasmic reticulum in living cells by bioorthogonal click reaction with a DBCO-labeled fluorophore revealing that the incorporated analogue is mainly localized in the endoplasmic membrane like the endogenous species. A LC-MS(/MS)-based microsomal in vitro assay confirmed that omega-azidosphinganine mimics the natural species enabling the identification and analysis of metabolic breakdown products of sphinganine as a key starting intermediate in the complex sphingolipid biosynthetic pathways. Furthermore, the sphinganine-fluorophore conjugate after click reaction was enzymatically tolerated to form its dihydroceramide and ceramide metabolites. Thus, omega-azidosphinganine represents a useful biofunctional tool for metabolic investigations both by in vivo fluorescence imaging of the sphingolipid subcellular localization in the ER and by in vitro high-resolution mass spectrometry analysis. This should reveal novel insights of the molecular mechanisms sphingolipids and their processing enzymes have e.g. in infection. Y1 - 2021 U6 - https://doi.org/10.1039/d0ob02592e SN - 1477-0520 SN - 1477-0539 VL - 19 IS - 10 SP - 2203 EP - 2212 PB - Royal Society of Chemistry CY - Cambridge ER - TY - JOUR A1 - Müller, S. M. A1 - Finke, Hannah A1 - Ebert, Franziska A1 - Kopp, Johannes Florian A1 - Schumacher, Fabian A1 - Kleuser, Burkhard A1 - Francesconi, Kevin A. A1 - Raber, G. A1 - Schwerdtle, Tanja T1 - Arsenic-containing hydrocarbons BT - effects on gene expression, epigenetics, and biotransformation in HepG2 cells JF - Archives of toxicology : official journal of EUROTOX N2 - Arsenic-containing hydrocarbons (AsHCs), a subgroup of arsenolipids found in fish and algae, elicit substantial toxic effects in various human cell lines and have a considerable impact on cellular energy levels. The underlying mode of action, however, is still unknown. The present study analyzes the effects of two AsHCs (AsHC 332 and AsHC 360) on the expression of 44 genes covering DNA repair, stress response, cell death, autophagy, and epigenetics via RT-qPCR in human liver (HepG2) cells. Both AsHCs affected the gene expression, but to different extents. After treatment with AsHC 360, flap structure-specific endonuclease 1 (FEN1) as well as xeroderma pigmentosum group A complementing protein (XPA) and (cytosine-5)-methyltransferase 3A (DNMT3A) showed time- and concentration-dependent alterations in gene expression, thereby indicating an impact on genomic stability. In the subsequent analysis of epigenetic markers, within 72 h, neither AsHC 332 nor AsHC 360 showed an impact on the global DNA methylation level, whereas incubation with AsHC 360 increased the global DNA hydroxymethylation level. Analysis of cell extracts and cell media by HPLC-mass spectrometry revealed that both AsHCs were considerably biotransformed. The identified metabolites include not only the respective thioxo-analogs of the two AsHCs, but also several arsenic-containing fatty acids and fatty alcohols, contributing to our knowledge of biotransformation mechanisms of arsenolipids. KW - Arsenolipids KW - Gene expression KW - Arsenic-containing hydrocarbons KW - Global DNA methylation KW - Arsenic speciation KW - Metabolism Y1 - 2018 U6 - https://doi.org/10.1007/s00204-018-2194-z SN - 0340-5761 SN - 1432-0738 VL - 92 IS - 5 SP - 1751 EP - 1765 PB - Springer CY - Heidelberg ER - TY - JOUR A1 - Gulbins, Anne A1 - Schumacher, Fabian A1 - Becker, Katrin Anne A1 - Wilker, Barbara A1 - Soddemann, Matthias A1 - Boldrin, Francesco A1 - Müller, Christian P. A1 - Edwards, Michael J. A1 - Goodman, Michael A1 - Caldwell, Charles C. A1 - Kleuser, Burkhard A1 - Kornhuber, Johannes A1 - Szabo, Ildiko A1 - Gulbins, Erich T1 - Antidepressants act by inducing autophagy controlled by sphingomyelin-ceramide JF - Molecular psychiatry N2 - Major depressive disorder (MDD) is a common and severe disease characterized by mood changes, somatic alterations, and often suicide. MDD is treated with antidepressants, but the molecular mechanism of their action is unknown. We found that widely used antidepressants such as amitriptyline and fluoxetine induce autophagy in hippocampal neurons via the slow accumulation of sphingomyelin in lysosomes and Golgi membranes and of ceramide in the endoplasmic reticulum (ER). ER ceramide stimulates phosphatase 2A and thereby the autophagy proteins Ulk, Beclin, Vps34/Phosphatidylinositol 3-kinase, p62, and Lc3B. Although treatment with amitriptyline or fluoxetine requires at least 12 days to achieve sphingomyelin accumulation and the subsequent biochemical and cellular changes, direct inhibition of sphingomyelin synthases with tricyclodecan-9-yl-xanthogenate (D609) results in rapid (within 3 days) accumulation of ceramide in the ER, activation of autophagy, and reversal of biochemical and behavioral signs of stress-induced MDD. Inhibition of Beclin blocks the antidepressive effects of amitriptyline and D609 and induces cellular and behavioral changes typical of MDD. These findings identify sphingolipid-controlled autophagy as an important target for antidepressive treatment methods and provide a rationale for the development of novel antidepressants that act within a few days. Y1 - 2018 U6 - https://doi.org/10.1038/s41380-018-0090-9 SN - 1359-4184 SN - 1476-5578 VL - 23 IS - 12 SP - 2324 EP - 2346 PB - Nature Publ. Group CY - London ER - TY - GEN A1 - Beckmann, Nadine A1 - Becker, Katrin Anne A1 - Kadow, Stephanie A1 - Schumacher, Fabian A1 - Kramer, Melanie A1 - Kühn, Claudine A1 - Schulz-Schaeffer, Walter J. A1 - Edwards, Michael J. A1 - Kleuser, Burkhard A1 - Gulbins, Erich A1 - Carpinteiro, Alexander T1 - Acid sphingomyelinase deficiency ameliorates Farber disease T2 - Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe N2 - Farber disease is a rare lysosomal storage disorder resulting from acid ceramidase deficiency and subsequent ceramide accumulation. No treatments for Farber disease are clinically available, and affected patients have a severely shortened lifespan. We have recently reported a novel acid ceramidase deficiency model that mirrors the human disease closely. Acid sphingomyelinase is the enzyme that generates ceramide upstream of acid ceramidase in the lysosomes. Using our acid ceramidase deficiency model, we tested if acid sphingomyelinase could be a potential novel therapeutic target for the treatment of Farber disease. A number of functional acid sphingomyelinase inhibitors are clinically available and have been used for decades to treat major depression. Using these as a therapeutic for Farber disease, thus, has the potential to improve central nervous symptoms of the disease as well, something all other treatment options for Farber disease can’t achieve so far. As a proof-of-concept study, we first cross-bred acid ceramidase deficient mice with acid sphingomyelinase deficient mice in order to prevent ceramide accumulation. Double-deficient mice had reduced ceramide accumulation, fewer disease manifestations, and prolonged survival. We next targeted acid sphingomyelinase pharmacologically, to test if these findings would translate to a setting with clinical applicability. Surprisingly, the treatment of acid ceramidase deficient mice with the acid sphingomyelinase inhibitor amitriptyline was toxic to acid ceramidase deficient mice and killed them within a few days of treatment. In conclusion, our study provides the first proof-of-concept that acid sphingomyelinase could be a potential new therapeutic target for Farber disease to reduce disease manifestations and prolong survival. However, we also identified previously unknown toxicity of the functional acid sphingomyelinase inhibitor amitriptyline in the context of Farber disease, strongly cautioning against the use of this substance class for Farber disease patients T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 1087 KW - Farber disease KW - lysosomal storage disorders KW - acid ceramidase KW - acid sphingomyelinase KW - amitriptyline Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-441282 SN - 1866-8372 IS - 1087 ER - TY - JOUR A1 - Beckmann, Nadine A1 - Becker, Katrin Anne A1 - Kadow, Stephanie A1 - Schumacher, Fabian A1 - Kramer, Melanie A1 - Kuehn, Claudine A1 - Schulz-Schaeffer, Walter J. A1 - Edwards, Michael J. A1 - Kleuser, Burkhard A1 - Gulbins, Erich A1 - Carpinteiro, Alexander T1 - Acid Sphingomyelinase Deficiency Ameliorates Farber Disease JF - International journal of molecular sciences N2 - Farber disease is a rare lysosomal storage disorder resulting from acid ceramidase deficiency and subsequent ceramide accumulation. No treatments for Farber disease are clinically available, and affected patients have a severely shortened lifespan. We have recently reported a novel acid ceramidase deficiency model that mirrors the human disease closely. Acid sphingomyelinase is the enzyme that generates ceramide upstream of acid ceramidase in the lysosomes. Using our acid ceramidase deficiency model, we tested if acid sphingomyelinase could be a potential novel therapeutic target for the treatment of Farber disease. A number of functional acid sphingomyelinase inhibitors are clinically available and have been used for decades to treat major depression. Using these as a therapeutic for Farber disease, thus, has the potential to improve central nervous symptoms of the disease as well, something all other treatment options for Farber disease can’t achieve so far. As a proof-of-concept study, we first cross-bred acid ceramidase deficient mice with acid sphingomyelinase deficient mice in order to prevent ceramide accumulation. Double-deficient mice had reduced ceramide accumulation, fewer disease manifestations, and prolonged survival. We next targeted acid sphingomyelinase pharmacologically, to test if these findings would translate to a setting with clinical applicability. Surprisingly, the treatment of acid ceramidase deficient mice with the acid sphingomyelinase inhibitor amitriptyline was toxic to acid ceramidase deficient mice and killed them within a few days of treatment. In conclusion, our study provides the first proof-of-concept that acid sphingomyelinase could be a potential new therapeutic target for Farber disease to reduce disease manifestations and prolong survival. However, we also identified previously unknown toxicity of the functional acid sphingomyelinase inhibitor amitriptyline in the context of Farber disease, strongly cautioning against the use of this substance class for Farber disease patients. KW - Farber disease KW - lysosomal storage disorders KW - acid ceramidase KW - acid sphingomyelinase KW - amitriptyline Y1 - 2019 U6 - https://doi.org/10.3390/ijms20246253 SN - 1422-0067 VL - 20 IS - 24 PB - MDPI CY - Basel ER - TY - JOUR A1 - Zeitler, Stefanie A1 - Ye, Lian A1 - Andreyeva, Aksana A1 - Schumacher, Fabian A1 - Monti, Juliana A1 - Nürnberg, Bernd A1 - Nowak, Gabriel A1 - Kleuser, Burkhard A1 - Reichel, Martin A1 - Fejtova, Anna A1 - Kornhuber, Johannes A1 - Rhein, Cosima A1 - Friedland, Kristina T1 - Acid sphingomyelinase - a regulator of canonical transient receptor potential channel 6 (TRPC6) activity JF - Journal of neurochemistry N2 - Recent investigations propose the acid sphingomyelinase (ASM)/ceramide system as a novel target for antidepressant action. ASM catalyzes the breakdown of the abundant membrane lipid sphingomyelin to the lipid messenger ceramide. This ASM‐induced lipid modification induces a local shift in membrane properties, which influences receptor clustering and downstream signaling. Canonical transient receptor potential channels 6 (TRPC6) are non‐selective cation channels located in the cell membrane that play an important role in dendritic growth, synaptic plasticity and cognition in the brain. They can be activated by hyperforin, an ingredient of the herbal remedy St. John’s wort for treatment of depression disorders. Because of their role in the context of major depression, we investigated the crosstalk between the ASM/ceramide system and TRPC6 ion channels in a pheochromocytoma cell line 12 neuronal cell model (PC12 rat pheochromocytoma cell line). Ca2+ imaging experiments indicated that hyperforin‐induced Ca2+ influx through TRPC6 channels is modulated by ASM activity. While antidepressants, known as functional inhibitors of ASM activity, reduced TRPC6‐mediated Ca2+ influx, extracellular application of bacterial sphingomyelinase rebalanced TRPC6 activity in a concentration‐related way. This effect was confirmed in whole‐cell patch clamp electrophysiology recordings. Lipidomic analyses revealed a decrease in very long chain ceramide/sphingomyelin molar ratio after ASM inhibition, which was connected with changes in the abundance of TRPC6 channels in flotillin‐1–positive lipid rafts as visualized by western blotting. Our data provide evidence that the ASM/ceramide system regulates TRPC6 channels likely by controlling their recruitment to specific lipid subdomains and thereby fine‐tuning their physical properties. KW - acid sphingomyelinase KW - antidepressants KW - ceramide KW - hyperforin KW - lipid rafts KW - TRPC6 Y1 - 2019 U6 - https://doi.org/10.1111/jnc.14823 SN - 0022-3042 SN - 1471-4159 VL - 150 IS - 6 SP - 678 EP - 690 PB - Wiley CY - Hoboken ER - TY - GEN A1 - Lang, Judith A1 - Bohn, Patrick A1 - Bhat, Hilal A1 - Jastrow, Holger A1 - Walkenfort, Bernd A1 - Cansiz, Feyza A1 - Fink, Julian A1 - Bauer, Michael A1 - Schumacher, Fabian A1 - Kleuser, Burkhard A1 - Lang, Karl S. T1 - Acid ceramidase of macrophages traps herpes simplex virus in multivesicular bodies and protects from severe disease T2 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe N2 - Macrophages have important protective functions during infection with herpes simplex virus type 1 (HSV-1). However, molecular mechanisms that restrict viral propagation and protect from severe disease are unclear. Here we show that macrophages take up HSV-1 via endocytosis and transport the virions into multivesicular bodies (MVBs). In MVBs, acid ceramidase (aCDase) converts ceramide into sphingosine and increases the formation of sphingosine-rich intraluminal vesicles (ILVs). Once HSV-1 particles reach MVBs, sphingosine-rich ILVs bind to HSV-1 particles, which restricts fusion with the limiting endosomal membrane and prevents cellular infection. Lack of aCDase in macrophage cultures or in Asah1(-/-) mice results in replication of HSV-1 and Asah1(-/-) mice die soon after systemic or intravaginal inoculation. The treatment of macrophages with sphingosine enhancing compounds blocks HSV-1 propagation, suggesting a therapeutic potential of this pathway. In conclusion, aCDase loads ILVs with sphingosine, which prevents HSV-1 capsids from penetrating into the cytosol. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 1400 KW - immunology KW - infection KW - membrane fusion KW - phagocytosis KW - sphingolipids Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-515661 SN - 1866-8372 IS - 1 ER - TY - JOUR A1 - Lang, Judith A1 - Bohn, Patrick A1 - Bhat, Hilal A1 - Jastrow, Holger A1 - Walkenfort, Bernd A1 - Cansiz, Feyza A1 - Fink, Julian A1 - Bauer, Michael A1 - Schumacher, Fabian A1 - Kleuser, Burkhard A1 - Lang, Karl S. T1 - Acid ceramidase of macrophages traps herpes simplex virus in multivesicular bodies and protects from severe disease JF - Nature Communications N2 - Macrophages have important protective functions during infection with herpes simplex virus type 1 (HSV-1). However, molecular mechanisms that restrict viral propagation and protect from severe disease are unclear. Here we show that macrophages take up HSV-1 via endocytosis and transport the virions into multivesicular bodies (MVBs). In MVBs, acid ceramidase (aCDase) converts ceramide into sphingosine and increases the formation of sphingosine-rich intraluminal vesicles (ILVs). Once HSV-1 particles reach MVBs, sphingosine-rich ILVs bind to HSV-1 particles, which restricts fusion with the limiting endosomal membrane and prevents cellular infection. Lack of aCDase in macrophage cultures or in Asah1(-/-) mice results in replication of HSV-1 and Asah1(-/-) mice die soon after systemic or intravaginal inoculation. The treatment of macrophages with sphingosine enhancing compounds blocks HSV-1 propagation, suggesting a therapeutic potential of this pathway. In conclusion, aCDase loads ILVs with sphingosine, which prevents HSV-1 capsids from penetrating into the cytosol. KW - immunology KW - infection KW - membrane fusion KW - phagocytosis KW - sphingolipids Y1 - 2020 U6 - https://doi.org/10.1038/s41467-020-15072-8 SN - 2041-1723 VL - 11 IS - 1 SP - 1 EP - 15 PB - Nature Publishing Group UK CY - London ER - TY - JOUR A1 - Chmielewski, Frank M. A1 - Baldermann, Susanne A1 - Götz, Klaus Peter A1 - Homann, Thomas A1 - Gödeke, Kristin A1 - Schumacher, Fabian A1 - Huschek, Gerd A1 - Rawel, Harshadrai Manilal T1 - Abscisic acid related metabolites in sweet cherry buds (Prunus avium L.) JF - Journal of Horticulture N2 - As our climate changes, plant mechanisms involved for dormancy release become increasingly important for commercial orchards. It is generally believed that abscisic acid (ABA) is a key hormone that responds to various environmental stresses which affects bud dormancy. For this reason, a multi-year study was initiated to obtain data on plant metabolites during winter rest and ontogenetic development in sweet cherry buds (Prunus avium L.). In this paper, we report on metabolites involved in ABA synthesis and catabolism and its effect on bud dormancy in the years 2014/15-2016/17. In previous work, the timings of the different phases of para-, endo-, ecodormancy and ontogenetic development for cherry flower buds of the cultivar ‘Summit’ were determined, based on classical climate chamber experiments and changes in the bud’s water content. Based on these time phases, we focused now on the different aspects of the ABA-metabolism. The results show that there is a continual synthesis of ABA about 5 weeks before leaf fall, and a degradation of ABA during ecodormancy and bud development until the phenological stage ‘open cluster’. This is confirmed by relating the ABA content to that of the total precursor carotenoids, neoxanthin and violaxanthin. The tentative monitoring of individual intermediate metabolites revealed that dihydroxyphaseic acid is the most abundant catabolite of ABA and ABA glucosyl ester is in terms of mass intensity, the most abundant ABA metabolite observed in this study. The results suggest that the direct route for ABA biosynthesis from farnesyl pyrophosphate may also be relevant in cherry flower buds. KW - Dormancy KW - Abscisic acid KW - Synthesis KW - Catabolism KW - Prunus avium L. KW - Flower buds Y1 - 2018 U6 - https://doi.org/10.4172/2376-0354.1000221 SN - 2376-0354 VL - 5 IS - 1 ER - TY - JOUR A1 - Solger, Franziska A1 - Kunz, Tobias C. A1 - Fink, Julian A1 - Paprotka, Kerstin A1 - Pfister, Pauline A1 - Hagen, Franziska A1 - Schumacher, Fabian A1 - Kleuser, Burkhard A1 - Seibel, Jürgen A1 - Rudel, Thomas T1 - A role of sphingosine in the intracellular survival of Neisseria gonorrhoeae JF - Frontiers in Cellular and Infection Microbiology N2 - Obligate human pathogenic Neisseria gonorrhoeae are the second most frequent bacterial cause of sexually transmitted diseases. These bacteria invade different mucosal tissues and occasionally disseminate into the bloodstream. Invasion into epithelial cells requires the activation of host cell receptors by the formation of ceramide-rich platforms. Here, we investigated the role of sphingosine in the invasion and intracellular survival of gonococci. Sphingosine exhibited an anti-gonococcal activity in vitro. We used specific sphingosine analogs and click chemistry to visualize sphingosine in infected cells. Sphingosine localized to the membrane of intracellular gonococci. Inhibitor studies and the application of a sphingosine derivative indicated that increased sphingosine levels reduced the intracellular survival of gonococci. We demonstrate here, that sphingosine can target intracellular bacteria and may therefore exert a direct bactericidal effect inside cells. KW - Neisseria gonorrhoeae KW - sphingosine KW - sphingolipids KW - sphingosine kinases KW - invasion KW - survival KW - click chemistry Y1 - 2020 U6 - https://doi.org/10.3389/fcimb.2020.00215 SN - 2235-2988 VL - 10 PB - Frontiers Media CY - Lausanne ER - TY - JOUR A1 - Wiesner-Reinhold, Melanie A1 - Barknowitz, Gitte A1 - Florian, Simone A1 - Mewis, Inga A1 - Schumacher, Fabian A1 - Schreiner, Monika A1 - Glatt, Hansruedi T1 - 1-Methoxy-3-indolylmethyl DNA adducts in six tissues, and blood protein adducts, in mice under pak choi diet: time course and persistence JF - Archives of toxicology : official journal of EUROTOX N2 - We previously showed that purified 1-methoxy-3-indolylmethyl (1-MIM) glucosinolate, a secondary plant metabolite in Brassica species, is mutagenic in various in vitro systems and forms DNA and protein adducts in mouse models. In the present study, we administered 1-MIM glucosinolate in a natural matrix to mice, by feeding a diet containing pak choi powder and extract. Groups of animals were killed after 1, 2, 4 and 8 days of pak choi diet, directly or, in the case of the 8-day treatment, after 0, 8 and 16 days of recovery with pak choi-free diet. DNA adducts [N-2-(1-MIM)-dG, N-6-(1-MIM)-dA] in six tissues, as well as protein adducts [tau N-(1-MIM)-His] in serum albumin (SA) and hemoglobin (Hb) were determined using UPLC-MS/MS with isotopically labeled internal standards. None of the samples from the 12 control animals under standard diet contained any 1-MIM adducts. All groups receiving pak choi diet showed DNA adducts in all six tissues (exception: lung of mice treated for a single day) as well as SA and Hb adducts. During the feeding period, all adduct levels continuously increased until day 8 (in the jejunum until day 4). During the 14-day recovery period, N-2-(1-MIM)-dG in liver, kidney, lung, jejunum, cecum and colon decreased to 52, 41, 59, 11, 7 and 2%, respectively, of the peak level. The time course of N-6-(1-MIM)-dA was similar. Immunohistochemical analyses indicated that cell turnover is a major mechanism of DNA adduct elimination in the intestine. In the same recovery period, protein adducts decreased more rapidly in SA than in Hb, to 0.7 and 37%, respectively, of the peak level, consistent with the differential turnover of these proteins. In conclusion, the pak choi diet lead to the formation of high levels of adducts in mice. Cell and protein turnover was a major mechanism of adduct elimination, at least in gut and blood. KW - 1-Methoxy-3-indolylmethyl glucosinolate KW - Neoglucobrassicin KW - DNA adducts KW - Blood protein adducts KW - Pak choi Y1 - 2019 U6 - https://doi.org/10.1007/s00204-019-02452-3 SN - 0340-5761 SN - 1432-0738 VL - 93 IS - 6 SP - 1515 EP - 1527 PB - Springer CY - Heidelberg ER -