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  - 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  - 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  - 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  - 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  - 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  - 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  - 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  -