TY  - JOUR
A1  - Bhabak, Krishna P.
A1  - Kleuser, Burkhard
A1  - Huwiler, Andrea
A1  - Arenz, Christoph
T1  - Effective inhibition of acid and neutral ceramidases by novel B-13 and LCL-464 analogues
JF  - Bioorganic & medicinal chemistry : a Tetrahedron publication for the rapid dissemination of full original research papers and critical reviews on biomolecular chemistry, medicinal chemistry and related disciplines
N2  - Induction of apoptosis mediated by the inhibition of ceramidases has been shown to enhance the efficacy of conventional chemotherapy in several cancer models. Among the inhibitors of ceramidases reported in the literature, B-13 is considered as a lead compound having good in vitro potency towards acid ceramidase. Furthermore, owing to the poor activity of B-13 on lysosoamal acid ceramidase in living cells, LCL-464 a modified derivative of B-13 containing a basic omega-amino group at the fatty acid was reported to have higher potency towards lysosomal acid ceramidase in living cells. In a search for more potent inhibitors of ceramidases, we have designed a series of compounds with structural modifications of B-13 and LCL-464. In this study, we show that the efficacy of B-13 in vitro as well as in intact cells can be enhanced by suitable modification of functional groups. Furthermore, a detailed SAR investigation on LCL-464 analogues revealed novel promising inhibitors of aCDase and nCDase. In cell culture studies using the breast cancer cell line MDA-MB-231, some of the newly developed compounds elevated endogenous ceramide levels and in parallel, also induced apoptotic cell death. In summary, this study shows that structural modification of the known ceramidase inhibitors B-13 and LCL-464 generates more potent ceramidase inhibitors that are active in intact cells and not only elevates the cellular ceramide levels, but also enhances cell death.
KW  - Sphingolipids
KW  - Ceramide
KW  - Ceramidase inhibitors
KW  - Structure-activity-relationship
Y1  - 2013
U6  - https://doi.org/10.1016/j.bmc.2012.12.014
SN  - 0968-0896
VL  - 21
IS  - 4
SP  - 874
EP  - 882
PB  - Elsevier
CY  - Oxford
ER  - 
TY  - GEN
A1  - Polzin, Amin
A1  - Rassaf, Tienush
A1  - Boehm, Andreas
A1  - Lueth, Anja
A1  - Kleuser, Burkhard
A1  - Zeus, Tobias
A1  - Kelm, Malte
A1  - Kroemer, Heyo K.
A1  - Schroer, Karsten
A1  - Rauch, Bernhard H.
T1  - Aspirin inhibits release of platelet-derived sphingosine-1-phosphate in
 acute myocardial infarction
T2  - INTERNATIONAL JOURNAL OF CARDIOLOGY
KW  - Sphingosine-1-phosphate
KW  - Acute coronary syndrome
KW  - Platelets
KW  - Aspirin
Y1  - 2013
U6  - https://doi.org/10.1016/j.ijcard.2013.10.050
SN  - 0167-5273
SN  - 1874-1754
VL  - 170
IS  - 2
SP  - E23
EP  - E24
PB  - ELSEVIER IRELAND LTD
CY  - CLARE
ER  - 
TY  - JOUR
A1  - Gulbins, Erich
A1  - Palmada, Monica
A1  - Reichel, Martin
A1  - Lueth, Anja
A1  - Boehmer, Christoph
A1  - Amato, Davide
A1  - Mueller, Christian P.
A1  - Tischbirek, Carsten H.
A1  - Groemer, Teja W.
A1  - Tabatabai, Ghazaleh
A1  - Becker, Katrin Anne
A1  - Tripal, Philipp
A1  - Staedtler, Sven
A1  - Ackermann, Teresa F.
A1  - van Brederode, Johannes
A1  - Alzheimer, Christian
A1  - Weller, Michael
A1  - Lang, Undine E.
A1  - Kleuser, Burkhard
A1  - Grassme, Heike
A1  - Kornhuber, Johannes
T1  - Acid sphingomyelinase-ceramide system mediates effects of antidepressant drugs
JF  - Nature medicine
N2  - Major depression is a highly prevalent severe mood disorder that is treated with antidepressants. The molecular targets of antidepressants require definition. We investigated the role of the acid sphingomyelinase (Asm)-ceramide system as a target for antidepressants. Therapeutic concentrations of the antidepressants amitriptyline and fluoxetine reduced Asm activity and ceramide concentrations in the hippocampus, increased neuronal proliferation, maturation and survival and improved behavior in mouse models of stress-induced depression. Genetic Asm deficiency abrogated these effects. Mice overexpressing Asm, heterozygous for acid ceramidase, treated with blockers of ceramide metabolism or directly injected with C16 ceramide in the hippocampus had higher ceramide concentrations and lower rates of neuronal proliferation, maturation and survival compared with controls and showed depression-like behavior even in the absence of stress. The decrease of ceramide abundance achieved by antidepressant-mediated inhibition of Asm normalized these effects. Lowering ceramide abundance may thus be a central goal for the future development of antidepressants.
Y1  - 2013
U6  - https://doi.org/10.1038/nm.3214
SN  - 1078-8956
VL  - 19
IS  - 7
SP  - 934
EP  - +
PB  - Nature Publ. Group
CY  - New York
ER  - 
TY  - JOUR
A1  - Böhm, Andreas
A1  - Flößer, Anja
A1  - Ermler, Swen
A1  - Fender, Anke C.
A1  - Lüth, Anja
A1  - Kleuser, Burkhard
A1  - Schrör, Karsten
A1  - Rauch, Bernhard H.
T1  - Factor-Xa-induced mitogenesis and migration require sphingosine kinase activity and S1P formation in human vascular smooth muscle cells
JF  - Cardiovascular research
N2  - Sphingosine-1-phosphate (S1P) is a cellular signalling lipid generated by sphingosine kinase-1 (SPHK1). The aim of the study was to investigate whether the activated coagulation factor-X (FXa) regulates SPHK1 transcription and the formation of S1P and subsequent mitogenesis and migration of human vascular smooth muscle cells (SMC).
 FXa induced a time- (36 h) and concentration-dependent (330 nmol/L) increase of SPHK1 mRNA and protein expression in human aortic SMC, resulting in an increased synthesis of S1P. FXa-stimulated transcription of SPHK1 was mediated by the protease-activated receptor-1 (PAR-1) and PAR-2. In human carotid artery plaques, expression of SPHK1 was observed at SMC-rich sites and was co-localized with intraplaque FX/FXa content. FXa-induced SPHK1 transcription was attenuated by inhibitors of Rho kinase (Y27632) and by protein kinase C (PKC) isoforms (GF109203X). In addition, FXa rapidly induced the activation of the small GTPase Rho A. Inhibition of signalling pathways which regulate SPHK1 expression, inhibition of its activity or siRNA-mediated SPHK1 knockdown attenuated the mitogenic and chemotactic response of human SMC to FXa.
 These data suggest that FXa induces SPHK1 expression and increases S1P formation independent of thrombin and that this involves the activation of Rho A and PKC signalling. In addition to its key function in coagulation, this direct effect of FXa on human SMC may increase cell proliferation and migration at sites of vessel injury and thereby contribute to the progression of vascular lesions.
KW  - Factor-Xa
KW  - Atherosclerosis
KW  - Proliferation
KW  - Smooth muscle cells
KW  - Sphingosine kinase-1
Y1  - 2013
U6  - https://doi.org/10.1093/cvr/cvt112
SN  - 0008-6363
VL  - 99
IS  - 3
SP  - 505
EP  - 513
PB  - Oxford Univ. Press
CY  - Oxford
ER  - 
TY  - JOUR
A1  - Schaper, Katrin
A1  - Dickhaut, Jeannette
A1  - Japtok, Lukasz
A1  - Kietzmann, Manfred
A1  - Mischke, Reinhard
A1  - Kleuser, Burkhard
A1  - Bäumer, Wolfgang
T1  - Sphingosine-1-phosphate exhibits anti-proliferative and anti-inflammatory effects in mouse models of psoriasis
JF  - Journal of dermatological scienc
N2  - Background: It has been indicated that the sphingolipid sphingosine-1-phosphate (SIP) restrains the ability of dendritic cells to migrate to lymph nodes. Furthermore SIP has been demonstrated to inhibit cell growth in human keratinocytes. However, only little is known about the effect of S1P in hyperproliferative and inflammatory in vivo models.
 Objective: In this study, locally acting SIP was explored in different experimental mouse models of psoriasis vulgaris.
 Methods: S1P and FTY720 were tested in the imiquimod-induced psoriasis mouse model, the mouse tail assay and a pilot study of the severe combined immunodeficiency mice (SCID).
 Results: In the imiquimod model the positive control diflorasone diacetate and S1P, but not FTY720 reduced the imiquimod-induced epidermal hyperproliferation of the ear skin. This effect was confirmed in the SCID model, where S1P treated skin from patients suffering from psoriasis showed a decrease in epidermal thickness compared to vehicle. In the imiquimod model, there was also significant inhibition of ear swelling and a moderate reduction of inflammatory cell influx and oedema formation in ear skin by SIP treatment. The inflammatory response on the back skin was, however, only reduced by diflorasone diacetate. In the mouse tail assay, the influence of S1P and FTY720 in stratum granulosum formation was tested compared to the positive control calcipotriol. Whereas topical administration of calcipotriol led to a low but significant increase of stratum granulosum, S1P and FTY720 lacked such an effect.
 Conclusion: Taken together, these results imply that topical administration of SIP might be a new option for the treatment of mild to moderate psoriasis lesions.
KW  - Imiquimod
KW  - Psoriasis
KW  - SCID mice
KW  - Sphingosine-1-phosphate
Y1  - 2013
U6  - https://doi.org/10.1016/j.jdermsci.2013.03.006
SN  - 0923-1811
VL  - 71
IS  - 1
SP  - 29
EP  - 36
PB  - Elsevier
CY  - Clare
ER  - 
TY  - JOUR
A1  - Putra, Sulistyo Emantoko Dwi
A1  - Neuber, Corinna
A1  - Reichetzeder, Christoph
A1  - Hocher, Berthold
A1  - Kleuser, Burkhard
T1  - Analysis of genomic DNA methylation levels in human placenta using liquid Chromatography-Electrospray ionization tandem mass spectrometry
JF  - Cellular physiology and biochemistry : international journal of experimental cellular physiology, biochemistry and pharmacology
N2  - Background: DNA-methylation is a common epigenetic tool which plays a crucial role in gene regulation and is essential for cell differentiation and embryonic development. The placenta is an important organ where gene activity can be regulated by epigenetic DNA modifications, including DNA methylation. This is of interest as, the placenta is the interface between the fetus and its environment, the mother. Exposure to environmental toxins and nutrition during pregnancy may alter DNA methylation of the placenta and subsequently placental function and as a result the phenotype of the offspring. The aim of this study was to develop a reliable method to quantify DNA methylation in large clinical studies. This will be a tool to analyze the degree of DNA methylation in the human placenta in relationship to clinical readouts. Methods: Liquid chromatography-electrospray ionization/multi-stage mass spectrometry (LC-ESI/MS/MS) technique was used for the quantification of the 5dmC/dG ratio in placentas from 248 healthy pregnancies. We were able to demonstrate that this method is a reliable and stable way to determine global placental DNA methylation in large clinical trials. Results/Conclusion: The degree of placental DNA methylation seen in our pilot study varies substantially from 2% to 5%. The clinical implications of this variation need to be demonstrated in adequately powered large studies.
KW  - Pregnancy
KW  - Placenta
KW  - Methylation
KW  - Global
KW  - LC-MS/MS
KW  - Fetal programming
KW  - Clinical
Y1  - 2014
U6  - https://doi.org/10.1159/000358666
SN  - 1015-8987
SN  - 1421-9778
VL  - 33
IS  - 4
SP  - 945
EP  - 952
PB  - Karger
CY  - Basel
ER  - 
TY  - CHAP
A1  - Arlt, Olga
A1  - Schwiebs, Anja
A1  - Pfarr, Kathrin
A1  - Ranglack, Annika
A1  - Bouzas, Ferreiros Nerea
A1  - Schreiber, Yannick
A1  - Neuber, Corinna
A1  - Kleuser, Burkhard
A1  - Pfeilschifter, Josef M.
A1  - Radeke, Heinfried H.
T1  - Dynamic interaction between sphingolipid enzymes, S1P and inflammatory cytokine regulation in dendritic cells
T2  - NAUNYN-SCHMIEDEBERGS ARCHIVES OF PHARMACOLOGY
Y1  - 2014
SN  - 0028-1298
SN  - 1432-1912
VL  - 387
SP  - S91
EP  - S91
PB  - Springer
CY  - New York
ER  - 
TY  - JOUR
A1  - Imeri, Faik
A1  - Fallegger, Daniel
A1  - Zivkovic, Aleksandra
A1  - Schwalm, Stephanie
A1  - Enzmann, Gaby
A1  - Blankenbach, Kira
A1  - Heringdorf, Dagmar Meyer Zu
A1  - Homann, Thomas
A1  - Kleuser, Burkhard
A1  - Pfeilschifter, Josef
A1  - Engelhardt, Britta
A1  - Stark, Holger
A1  - Huwiler, Andrea
T1  - Novel oxazolo-oxazole derivatives of FTY720 reduce endothelial cell permeability, immune cell chemotaxis and symptoms of experimental autoimmune encephalomyelitis in mice
JF  - Neuropharmacology
N2  - The immunomodulatory FTY720 (fingolimod) is presently approved for the treatment of relapsing-remitting multiple sclerosis. It is a prodrug that acts by modulating sphingosine 1-phosphate (S1P) receptor signaling. In this study, we have developed and characterized two novel oxazolo-oxazole derivatives of FTY720, ST-968 and the oxy analog ST-1071, which require no preceding activating phosphorylation, and proved to be active in intact cells and triggered S1P(1) and S1P(3), but not S1P(2), receptor internalization as a result of receptor activation.
 Functionally, ST-968 and ST-1071 acted similar to FTY720 to abrogate S1P-triggered chemotaxis of mouse splenocytes, mouse T cells and human U937 cells, and reduced TNFa- and LPS-stimulated endothelial cell permeability. The compounds also reduced TNF alpha-induced ICAM-1 and VCAM-1 mRNA expression, but restored TNF alpha-mediated downregulation of PECAM-1 mRNA expression.
 In an in vivo setting, the application of ST-968 or ST-1071 to mice resulted in a reduction of blood lymphocytes and significantly reduced the clinical symptoms of experimental autoimmune encephalomyelitis (EAE) in C57BL/6 mice comparable to FTY720 either by prophylactic or therapeutic treatment. In parallel to the reduced clinical symptoms, infiltration of immune cells in the brain was strongly reduced, and in isolated tissues of brain and spinal cord, the mRNA and protein expressions of ICAM-1 and VCAM-1, as well as of matrix metalloproteinase-9 were reduced by all compounds, whereas PECAM-1 and tissue inhibitor of metalloproteinase TIMP-1 were upregulated.
 In summary, the data suggest that these novel butterfly derivatives of FTY720 could have considerable implication for future therapies of multiple sclerosis and other autoimmune diseases. (C) 2014 Elsevier Ltd. All rights reserved.
KW  - Fingolimod
KW  - ST-968
KW  - ST-1071
KW  - Sphingosine 1-phosphate
KW  - Endothelial cells
KW  - Permeability
KW  - Multiple sclerosis
Y1  - 2014
U6  - https://doi.org/10.1016/j.neuropharm.2014.05.012
SN  - 0028-3908
SN  - 1873-7064
VL  - 85
SP  - 314
EP  - 327
PB  - Elsevier
CY  - Oxford
ER  - 
TY  - JOUR
A1  - Keller, Johannes
A1  - Catala-Lehnen, Philip
A1  - Huebner, Antje K.
A1  - Jeschke, Anke
A1  - Heckt, Timo
A1  - Lueth, Anja
A1  - Krause, Matthias
A1  - Koehne, Till
A1  - Albers, Joachim
A1  - Schulze, Jochen
A1  - Schilling, Sarah
A1  - Haberland, Michael
A1  - Denninger, Hannah
A1  - Neven, Mona
A1  - Hermans-Borgmeyer, Irm
A1  - Streichert, Thomas
A1  - Breer, Stefan
A1  - Barvencik, Florian
A1  - Levkau, Bodo
A1  - Rathkolb, Birgit
A1  - Wolf, Eckhard
A1  - Calzada-Wack, Julia
A1  - Neff, Frauke
A1  - Gailus-Durner, Valerie
A1  - Fuchs, Helmut
A1  - de Angelis, Martin Hrabe
A1  - Klutmann, Susanne
A1  - Tsourdi, Elena
A1  - Hofbauer, Lorenz C.
A1  - Kleuser, Burkhard
A1  - Chun, Jerold
A1  - Schinke, Thorsten
A1  - Amling, Michael
T1  - Calcitonin controls bone formation by inhibiting the release of sphingosine 1-phosphate from osteoclasts
JF  - Nature Communications
N2  - The hormone calcitonin (CT) is primarily known for its pharmacologic action as an inhibitor of bone resorption, yet CT-deficient mice display increased bone formation. These findings raised the question about the underlying cellular and molecular mechanism of CT action. Here we show that either ubiquitous or osteoclast-specific inactivation of the murine CT receptor (CTR) causes increased bone formation. CT negatively regulates the osteoclast expression of Spns2 gene, which encodes a transporter for the signalling lipid sphingosine 1-phosphate (S1P). CTR-deficient mice show increased S1P levels, and their skeletal phenotype is normalized by deletion of the S1P receptor S1P(3). Finally, pharmacologic treatment with the nonselective S1P receptor agonist FTY720 causes increased bone formation in wild-type, but not in S1P(3)-deficient mice. This study redefines the role of CT in skeletal biology, confirms that S1P acts as an osteoanabolic molecule in vivo and provides evidence for a pharmacologically exploitable crosstalk between osteoclasts and osteoblasts.
Y1  - 2014
U6  - https://doi.org/10.1038/ncomms6215
SN  - 2041-1723
VL  - 5
PB  - Nature Publ. Group
CY  - London
ER  - 
TY  - CHAP
A1  - Baranyai, Dorothea
A1  - Goedtel-Armbrust, Ute
A1  - Nestler, Sebastian
A1  - Kleuser, Burkhard
A1  - Wojnowski, Leszek
T1  - A role for cutaneous CYP3A in vitamin D homeostasis?
T2  - NAUNYN-SCHMIEDEBERGS ARCHIVES OF PHARMACOLOGY
Y1  - 2014
SN  - 0028-1298
SN  - 1432-1912
VL  - 387
SP  - S27
EP  - S27
PB  - Springer
CY  - New York
ER  - 
TY  - JOUR
A1  - Sic, Heiko
A1  - Kraus, Helene
A1  - Madl, Josef
A1  - Flittner, Karl-Andreas
A1  - von Muenchow, Audrey Lilly
A1  - Pieper, Kathrin
A1  - Rizzi, Marta
A1  - Kienzler, Anne-Kathrin
A1  - Ayata, Korcan
A1  - Rauer, Sebastian
A1  - Kleuser, Burkhard
A1  - Salzer, Ulrich
A1  - Burger, Meike
A1  - Zirlik, Katja
A1  - Lougaris, Vassilios
A1  - Plebani, Alessandro
A1  - Roemer, Winfried
A1  - Loeffler, Christoph
A1  - Scaramuzza, Samantha
A1  - Villa, Anna
A1  - Noguchi, Emiko
A1  - Grimbacher, Bodo
A1  - Eibel, Hermann
T1  - Sphingosine-1-phosphate receptors control B-cell migration through signaling components associated with primary immunodeficiencies, chronic lymphocytic leukemia, and multiple sclerosis
JF  - The journal of allergy and clinical immunology
N2  - Background: Five different G protein-coupled sphingosine-1-phosphate (S1P) receptors (S1P1-S1P5) regulate a variety of physiologic and pathophysiologic processes, including lymphocyte circulation, multiple sclerosis (MS), and cancer. Although B-lymphocyte circulation plays an important role in these processes and is essential for normal immune responses, little is known about S1P receptors in human B cells.
 Objective: To explore their function and signaling, we studied B-cell lines and primary B cells from control subjects, patients with leukemia, patients with S1P receptor inhibitor-treated MS, and patients with primary immunodeficiencies.
 Methods: S1P receptor expression was analyzed by using multicolor immunofluorescence microscopy and quantitative PCR. Transwell assays were used to study cell migration. S1P receptor internalization was visualized by means of time-lapse imaging with fluorescent S1P receptor fusion proteins expressed by using lentiviral gene transfer. B-lymphocyte subsets were characterized by means of flow cytometry and immunofluorescence microscopy.
 Results: Showing that different B-cell populations express different combinations of S1P receptors, we found that S1P1 promotes migration, whereas S1P4 modulates and S1P2 inhibits S1P1 signals. Expression of CD69 in activated B lymphocytes and B cells from patients with chronic lymphocytic leukemia inhibited S1P-induced migration. Studying B-cell lines, normal B lymphocytes, and B cells from patients with primary immunodeficiencies, we identified Bruton tyrosine kinase, beta-arrestin 2, LPS-responsive beige-like anchor protein, dedicator of cytokinesis 8, and Wiskott-Aldrich syndrome protein as critical signaling components downstream of S1P1.
 Conclusion: Thus S1P receptor signaling regulates human B-cell circulation and might be a factor contributing to the pathology of MS, chronic lymphocytic leukemia, and primary immunodeficiencies.
KW  - Sphingosine-1-phosphate
KW  - B cells
KW  - migration
KW  - autoimmunity
KW  - circulation
KW  - fingolimod
KW  - FTY720
KW  - primary immunodeficiencies
Y1  - 2014
U6  - https://doi.org/10.1016/j.jaci.2014.01.037
SN  - 0091-6749
SN  - 1097-6825
VL  - 134
IS  - 2
SP  - 420
EP  - +
PB  - Elsevier
CY  - New York
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  - Pastukhov, Oleksandr
A1  - Schwalm, Stephanie
A1  - Zangemeister-Wittke, Uwe
A1  - Fabbro, Doriano
A1  - Bornancin, Frederic
A1  - Japtok, Lukasz
A1  - Kleuser, Burkhard
A1  - Pfeilschifter, Josef
A1  - Huwiler, Andrea
T1  - The ceramide kinase inhibitor NVP-231 inhibits breast and lung cancer cell proliferation by inducing M phase arrest and subsequent cell death
JF  - British journal of pharmacology : journal of The British Pharmacological Society
N2  - Background and PurposeCeramide kinase (CerK) catalyzes the generation of ceramide-1-phosphate which may regulate various cellular functions, including inflammatory reactions and cell growth. Here, we studied the effect of a recently developed CerK inhibitor, NVP-231, on cancer cell proliferation and viability and investigated the role of cell cycle regulators implicated in these responses.
 Experimental ApproachThe breast and lung cancer cell lines MCF-7 and NCI-H358 were treated with increasing concentrations of NVP-231 and DNA synthesis, colony formation and cell death were determined. Flow cytometry was performed to analyse cell cycle distribution of cells and Western blot analysis was used to detect changes in cell cycle regulator expression and activation.
 Key ResultsIn both cell lines, NVP-231 concentration-dependently reduced cell viability, DNA synthesis and colony formation. Moreover it induced apoptosis, as measured by increased DNA fragmentation and caspase-3 and caspase-9 cleavage. Cell cycle analysis revealed that NVP-231 decreased the number of cells in S phase and induced M phase arrest with an increased mitotic index, as determined by increased histone H3 phosphorylation. The effect on the cell cycle was even more pronounced when NVP-231 treatment was combined with staurosporine. Finally, overexpression of CerK protected, whereas down-regulation of CerK with siRNA sensitized, cells for staurosporine-induced apoptosis.
 Conclusions and ImplicationsOur data demonstrate for the first time a crucial role for CerK in the M phase control in cancer cells and suggest its targeted inhibition, using drugs such as NVP-231, in combination with conventional pro-apoptotic chemotherapy.
Y1  - 2014
U6  - https://doi.org/10.1111/bph.12886
SN  - 0007-1188
SN  - 1476-5381
VL  - 171
IS  - 24
SP  - 5829
EP  - 5844
PB  - Wiley-Blackwell
CY  - Hoboken
ER  - 
TY  - JOUR
A1  - Pewzner-Jung, Yael
A1  - Tabazavareh, Shaghayegh Tavakoli
A1  - Grassme, Heike
A1  - Becker, Katrin Anne
A1  - Japtok, Lukasz
A1  - Steinmann, Joerg
A1  - Joseph, Tammar
A1  - Lang, Stephan
A1  - Tuemmler, Burkhard
A1  - Schuchman, Edward H.
A1  - Lentsch, Alex B.
A1  - Kleuser, Burkhard
A1  - Edwards, Michael J.
A1  - Futerman, Anthony H.
A1  - Gulbins, Erich
T1  - Sphingoid long chain bases prevent lung infection by Pseudomonas aeruginosa
JF  - EMBO molecular medicine
N2  - Cystic fibrosis patients and patients with chronic obstructive pulmonary disease, trauma, burn wound, or patients requiring ventilation are susceptible to severe pulmonary infection by Pseudomonas aeruginosa. Physiological innate defense mechanisms against this pathogen, and their alterations in lung diseases, are for the most part unknown. We now demonstrate a role for the sphingoid long chain base, sphingosine, in determining susceptibility to lung infection by P.aeruginosa. Tracheal and bronchial sphingosine levels were significantly reduced in tissues from cystic fibrosis patients and from cystic fibrosis mouse models due to reduced activity of acid ceramidase, which generates sphingosine from ceramide. Inhalation of mice with sphingosine, with a sphingosine analog, FTY720, or with acid ceramidase rescued susceptible mice from infection. Our data suggest that luminal sphingosine in tracheal and bronchial epithelial cells prevents pulmonary P.aeruginosa infection in normal individuals, paving the way for novel therapeutic paradigms based on inhalation of acid ceramidase or of sphingoid long chain bases in lung infection.
KW  - cystic fibrosis
KW  - long chain base
KW  - lung infection
KW  - Pseudomonas aeruginosa
KW  - sphingosine
Y1  - 2014
U6  - https://doi.org/10.15252/emmm.201404075
SN  - 1757-4676
SN  - 1757-4684
VL  - 6
IS  - 9
SP  - 1205
EP  - 1214
PB  - Wiley-Blackwell
CY  - Hoboken
ER  - 
TY  - JOUR
A1  - Fayyaz, Susann
A1  - Henkel, Janin
A1  - Japtok, Lukasz
A1  - Krämer, Stephanie
A1  - Damm, Georg
A1  - Seehofer, Daniel
A1  - Püschel, Gerhard Paul
A1  - Kleuser, Burkhard
T1  - Involvement of sphingosine 1-phosphate in palmitate-induced insulin resistance of hepatocytes via the S1P(2) receptor subtype
JF  - Diabetologia : journal of the European Association for the Study of Diabetes (EASD)
N2  - Enhanced plasma levels of NEFA have been shown to induce hepatic insulin resistance, which contributes to the development of type 2 diabetes. Indeed, sphingolipids can be formed via a de novo pathway from the saturated fatty acid palmitate and the amino acid serine. Besides ceramides, sphingosine 1-phosphate (S1P) has been identified as a major bioactive lipid mediator. Therefore, our aim was to investigate the generation and function of S1P in hepatic insulin resistance.
 The incorporation of palmitate into sphingolipids was performed by rapid-resolution liquid chromatography-MS/MS in primary human and rat hepatocytes. The influence of S1P and the involvement of S1P receptors in hepatic insulin resistance was examined in human and rat hepatocytes, as well as in New Zealand obese (NZO) mice.
 Palmitate induced an impressive formation of extra- and intracellular S1P in rat and human hepatocytes. An elevation of hepatic S1P levels was observed in NZO mice fed a high-fat diet. Once generated, S1P was able, similarly to palmitate, to counteract insulin signalling. The inhibitory effect of S1P was abolished in the presence of the S1P(2) receptor antagonist JTE-013 both in vitro and in vivo. In agreement with this, the immunomodulator FTY720-phosphate, which binds to all S1P receptors except S1P(2), was not able to inhibit insulin signalling.
 These data indicate that palmitate is metabolised by hepatocytes to S1P, which acts via stimulation of the S1P(2) receptor to impair insulin signalling. In particular, S1P(2) inhibition could be considered as a novel therapeutic target for the treatment of insulin resistance.
KW  - FTY720
KW  - Insulin signalling
KW  - Palmitate
KW  - S1P receptors
KW  - Sphingolipids
KW  - Sphingosine 1-phosphate
Y1  - 2014
U6  - https://doi.org/10.1007/s00125-013-3123-6
SN  - 0012-186X
SN  - 1432-0428
VL  - 57
IS  - 2
SP  - 373
EP  - 382
PB  - Springer
CY  - New York
ER  - 
TY  - JOUR
A1  - Arlt, Olga
A1  - Schwiebs, Anja
A1  - Japtok, Lukasz
A1  - Rueger, Katja
A1  - Katzy, Elisabeth
A1  - Kleuser, Burkhard
A1  - Radeke, Heinfried H.
T1  - Sphingosine-1-Phosphate modulates dendritic cell function: focus on non-migratory effects in vitro and in vivo
JF  - Cellular physiology and biochemistry : international journal of experimental cellular physiology, biochemistry and pharmacology
N2  - Dendritic cells (DCs) are the cutting edge in innate and adaptive immunity. The major functions of these antigen presenting cells are the capture, endosomal processing and presentation of antigens, providing them an exclusive ability to provoke adaptive immune responses and to induce and control tolerance. Immature DCs capture and process antigens, migrate towards secondary lymphoid organs where they present antigens to naive T cells in a well synchronized sequence of procedures referred to as maturation. Indeed, recent research indicated that sphingolipids are modulators of essential steps in DC homeostasis. It has been recognized that sphingolipids not only modulate the development of DC subtypes from precursor cells but also influence functional activities of DCs such as antigen capture, and cytokine profiling. Thus, it is not astonishing that sphingolipids and sphingolipid metabolism play a substantial role in inflammatory diseases that are modulated by DCs. Here we highlight the function of sphingosine 1-phosphate (S1P) on DC homeostasis and the role of SIP and SW metabolism in inflammatory diseases.
KW  - Sphingosine-1-phosphate
KW  - Dendritic cells
KW  - Fingolimod
KW  - IL-12
KW  - Inflammation
Y1  - 2014
U6  - https://doi.org/10.1159/000362982
SN  - 1015-8987
SN  - 1421-9778
VL  - 34
IS  - 1
SP  - 27
EP  - 44
PB  - Karger
CY  - Basel
ER  - 
TY  - JOUR
A1  - Fayyaz, Susann
A1  - Japtok, Lukasz
A1  - Kleuser, Burkhard
T1  - Divergent role of sphingosine 1-Phosphate on insulin resistance
JF  - Cellular physiology and biochemistry : international journal of experimental cellular physiology, biochemistry and pharmacology
N2  - Insulin resistance is a complex metabolic disorder in which insulin-sensitive tissues fail to respond to the physiological action of insulin. There is a strong correlation of insulin resistance and the development of type 2 diabetes both reaching epidemic proportions. Dysfunctional lipid metabolism is a hallmark of insulin resistance and a risk factor for several cardiovascular and metabolic disorders. Numerous studies in humans and rodents have shown that insulin resistance is associated with elevations of non-esterified fatty acids (NEFA) in the plasma. Moreover, bioactive lipid intermediates such as diacylglycerol (DAG) and ceramides appear to accumulate in response to NEFA, which may interact with insulin signaling. However, recent work has also indicated that sphingosine 1-phosphate (S1P), a breakdown product of ceramide, modulate insulin signaling in different cell types. In this review, we summarize the current state of knowledge about S1P and insulin signaling in insulin sensitive cells. A specific focus is put on the action of S1P on hepatocytes, pancreatic beta-cells and skeletal muscle cells. In particular, modulation of S1P-signaling can be considered as a potential therapeutic target for the treatment of insulin resistance and type 2 diabetes.
KW  - Sphingosine 1-phosphate (S1P)
KW  - Insulin resistance
KW  - Ceramides
KW  - Diacylglycerol (DAG)
KW  - Non-esterified fatty acids (NEFA)
KW  - Hepatocytes
KW  - Pancreatic cells
KW  - Skeletal muscle cells
Y1  - 2014
U6  - https://doi.org/10.1159/000362990
SN  - 1015-8987
SN  - 1421-9778
VL  - 34
IS  - 1
SP  - 134
EP  - 147
PB  - Karger
CY  - Basel
ER  - 
TY  - JOUR
A1  - Gerecke, Christian
A1  - Scholtka, Bettina
A1  - Loewenstein, Yvonne
A1  - Fait, Isabel
A1  - Gottschalk, Uwe
A1  - Rogoll, Dorothee
A1  - Melcher, Ralph
A1  - Kleuser, Burkhard
T1  - Hypermethylation of ITGA4, TFPI2 and VIMENTIN promoters is increased in inflamed colon tissue: putative risk markers for colitis-associated cancer
JF  - Journal of cancer research and clinical oncology : official organ of the Deutsche Krebsgesellschaft
N2  - Epigenetic silencing of tumor suppressor genes is involved in early transforming events and has a high impact on colorectal carcinogenesis. Likewise, colon cancers that derive from chronically inflamed bowel diseases frequently exhibit epigenetic changes. But there is little data about epigenetic aberrations causing colorectal cancer in chronically inflamed tissue. The aim of the present study was to evaluate the aberrant gain of methylation in the gene promoters of VIM, TFPI2 and ITGA4 as putative early markers in the development from inflamed tissue via precancerous lesions toward colorectal cancer.
 Initial screening of different cancer cell lines by using methylation-specific PCR revealed a putative colon cancer-specific methylation pattern. Additionally, a demethylation assay was performed to investigate the methylation-dependent gene silencing of ITGA4. The candidate markers were analyzed in colonic tissue specimens from patients with colorectal cancer (n = 15), adenomas (n = 76), serrated lesions (n = 13), chronic inflammation (n = 10) and normal mucosal samples (n = 9).
 A high methylation frequency of VIM (55.6 %) was observed in normal colon tissue, whereas ITGA4 and TFPI2 were completely unmethylated in controls. A significant gain of methylation frequency with progression of disease as well as an age-dependent effect was detectable for TFPI2. ITGA4 methylation frequency was high in precancerous and cancerous tissues as well as in inflammatory bowel diseases (IBD).
 The already established methylation marker VIM does not permit a specific and sensitive discrimination of healthy and neoplastic tissue. The methylation markers ITGA4 and TFPI2 seem to be suitable risk markers for inflammation-associated colon cancer.
KW  - Epigenetic
KW  - DNA methylation
KW  - Colon cancer
KW  - Colitis
KW  - Gastrointestinal tract
KW  - Biomarker
Y1  - 2015
U6  - https://doi.org/10.1007/s00432-015-1972-8
SN  - 0171-5216
SN  - 1432-1335
VL  - 141
IS  - 12
SP  - 2097
EP  - 2107
PB  - Springer
CY  - New York
ER  - 
TY  - JOUR
A1  - Schraplau, Anne
A1  - Schewe, Bettina
A1  - Neuschäfer-Rube, Frank
A1  - Ringel, Sebastian
A1  - Neuber, Corinna
A1  - Kleuser, Burkhard
A1  - Püschel, Gerhard Paul
T1  - Enhanced thyroid hormone breakdown in hepatocytes by mutual induction of the constitutive androstane receptor (CAR, NR1I3) and arylhydrocarbon receptor by benzo[a]pyrene and phenobarbital
JF  - Toxicology
N2  - Xenobiotics may interfere with the hypothalamic-pituitary-thyroid endocrine axis by inducing enzymes that inactivate thyroid hormones and thereby reduce the metabolic rate. This induction results from an activation of xeno-sensing nuclear receptors. The current study shows that benzo[a]pyrene, a frequent contaminant of processed food and activator of the arylhydrocarbon receptor (AhR) activated the promoter and induced the transcription of the nuclear receptor constitutive androstane receptor (CAR, NR1I3) in rat hepatocytes. Likewise, phenobarbital induced the AhR transcription. This mutual induction of the nuclear receptors enhanced the phenobarbital-dependent induction of the prototypic CAR target gene Cyp2b1 as well as the AhR-dependent induction of UDP-glucuronosyltransferases. In both cases, the induction by the combination of both xenobiotics was more than the sum of the induction by either substance alone. By inducing the AhR, phenobarbital enhanced the benzo[a]pyrene-dependent reduction of thyroid hormone half-life and the benzo[a]pyrene-dependent increase in the rate of thyroid hormone glucuronide formation in hepatocyte cultures. CAR ligands might thus augment the endocrine disrupting potential of AhR activators by an induction of the AhR. (C) 2014 Elsevier Ireland Ltd. All rights reserved.
KW  - Endocrine disruption
KW  - Xenobesity
KW  - Aryl-hydrocarbon receptor
KW  - Cyp2b1
KW  - Thyroid hormone
KW  - UDP-glucuronosyltransferase
Y1  - 2015
U6  - https://doi.org/10.1016/j.tox.2014.12.004
SN  - 0300-483X
VL  - 328
SP  - 21
EP  - 28
PB  - Elsevier
CY  - Clare
ER  - 
TY  - JOUR
A1  - Prüfer, Nicole
A1  - Kleuser, Burkhard
A1  - van der Giet, Markus
T1  - The role of serum amyloid A and sphingosine-1-phosphate on high-density lipoprotein functionality
JF  - Biological chemistry
N2  - The high-density lipoprotein (HDL) is one of the most important endogenous cardiovascular protective markers. HDL is an attractive target in the search for new pharmaceutical therapies and in the prevention of cardiovascular events. Some of HDL's anti-atherogenic properties are related to the signaling molecule sphingosine-1-phosphate (S1P), which plays an important role in vascular homeostasis. However, for different patient populations it seems more complicated. Significant changes in HDL's protective potency are reduced under pathologic conditions and HDL might even serve as a proatherogenic particle. Under uremic conditions especially there is a change in the compounds associated with HDL. S1P is reduced and acute phase proteins such as serum amyloid A (SAA) are found to be elevated in HDL. The conversion of HDL in inflammation changes the functional properties of HDL. High amounts of SAA are associated with the occurrence of cardiovascular diseases such as atherosclerosis. SAA has potent pro-atherogenic properties, which may have impact on HDL's biological functions, including cholesterol efflux capacity, antioxidative and anti-inflammatory activities. This review focuses on two molecules that affect the functionality of HDL. The balance between functional and dysfunctional HDL is disturbed after the loss of the protective sphingolipid molecule S1P and the accumulation of the acute-phase protein SAA. This review also summarizes the biological activities of lipid-free and lipid-bound SAA and its impact on HDL function.
KW  - atherosclerosis
KW  - high-density lipoprotein (HDL)
KW  - inflammation
KW  - serum amyloid A (SAA)
KW  - sphingosine-1-phosphate (S1P)
Y1  - 2015
U6  - https://doi.org/10.1515/hsz-2014-0192
SN  - 1431-6730
SN  - 1437-4315
VL  - 396
IS  - 6-7
SP  - 573
EP  - 583
PB  - De Gruyter
CY  - Berlin
ER  -