@article{FayyazJaptokSchumacheretal.2017,
  author    = {Fayyaz, Susann and Japtok, Lukasz and Schumacher, Fabian and Wigger, Dominik and Schulz, Tim Julius and Haubold, Kathrin and Gulbins, Erich and V{\"o}ller, Heinz and Kleuser, Burkhard},
  title     = {Lysophosphatidic acid inhibits insulin signaling in primary rat hepatocytes via the LPA(3) receptor subtype and is increased in obesity},
  series = {Cellular physiology and biochemistry : international journal of experimental cellular physiology, biochemistry and pharmacology},
  volume    = {43},
  journal   = {Cellular physiology and biochemistry : international journal of experimental cellular physiology, biochemistry and pharmacology},
  publisher = {Karger},
  address   = {Basel},
  issn      = {1015-8987},
  doi       = {10.1159/000480470},
  pages     = {445 -- 456},
  year      = {2017},
  abstract  = {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.},
  language  = {en}
}
@article{NeuberSchumacherGulbinsetal.2017,
  author    = {Neuber, Corinna and Schumacher, Fabian and Gulbins, Erich and Kleuser, Burkhard},
  title     = {Mass Spectrometric Determination of Fatty Aldehydes Exemplified by Monitoring the Oxidative Degradation of (2E)-Hexadecenal in HepG2 Cell Lysates},
  series = {Lipidomics},
  volume    = {125},
  journal   = {Lipidomics},
  publisher = {Humana Press},
  address   = {Totowa},
  isbn      = {978-1-4939-6946-3},
  issn      = {0893-2336},
  doi       = {10.1007/978-1-4939-6946-3_10},
  pages     = {147 -- 158},
  year      = {2017},
  abstract  = {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.},
  language  = {en}
}
@article{SchwiebsThomasKleuseretal.2017,
  author    = {Schwiebs, Anja and Thomas, Dominique Jeanette and Kleuser, Burkhard and Pfeilschifter, Josef and Radeke, Heinfried H.},
  title     = {Nuclear translocation of SGPP-1 and decrease of SGPL-1 activity contribute to sphingolipid rheostat regulation of inflammatory dendritic cells},
  series = {Mediators of inflammation},
  journal   = {Mediators of inflammation},
  publisher = {Hindawi Publishing Corp.},
  address   = {London},
  issn      = {0962-9351},
  doi       = {10.1155/2017/5187368},
  pages     = {10},
  year      = {2017},
  abstract  = {A balanced sphingolipid rheostat is indispensable for dendritic cell function and survival and thus initiation of an immune response. Sphingolipid levels are dynamically maintained by the action of sphingolipid enzymes of which sphingosine kinases, S1P phosphatases (SGPP-1/2) and S1P lyase (SGPL-1), are pivotal in the balance of S1P and sphingosine levels. In this study, we present that SGPP-1 and SGPL-1 are regulated in inflammatory dendritic cells and contribute to S1P fate. TLR-dependent activation caused SGPL-1 protein downregulation with subsequent decrease of enzymatic activity by two-thirds. In parallel, confocal fluorescence microscopy revealed that endogenous SGPP-1 was expressed in nuclei of naive dendritic cells and was translocated into the cytoplasmatic compartment upon inflammatory stimulation resulting in dephosphorylation of S1P. Mass spectrometric determination showed that a part of the resulting sphingosine was released from the cell, increasing extracellular levels. Another route of diminishing intracellular S1P was possibly taken by its export via ATP-binding cassette transporter C1 which was upregulated in array analysis, while the S1P transporter, spinster homolog 2, was not relevant in dendritic cells. These investigations newly describe the sequential expression and localization of the endogenous S1P regulators SGPP-1 and SGPL-1 and highlight their contribution to the sphingolipid rheostat in inflammation.},
  language  = {en}
}
@article{HoehnJerniganJaptoketal.2017,
  author    = {Hoehn, Richard S. and Jernigan, Peter L. and Japtok, Lukasz and Chang, Alex L. and Midura, Emily F. and Caldwell, Charles C. and Kleuser, Burkhard and Lentsch, Alex B. and Edwards, Michael J. and Gulbins, Erich and Pritts, Timothy A.},
  title     = {Acid sphingomyelinase inhibition in stored erythrocytes reduces transfusion-associated lung inflammation},
  series = {Annals of surgery : a monthly review of surgical science and practice},
  volume    = {265},
  journal   = {Annals of surgery : a monthly review of surgical science and practice},
  number    = {1},
  publisher = {Lippincott Williams \& Wilkins},
  address   = {Philadelphia},
  issn      = {0003-4932},
  doi       = {10.1097/SLA.0000000000001648},
  pages     = {218 -- 226},
  year      = {2017},
  abstract  = {Objective: We aimed to identify the role of the enzyme acid sphingomyelinase in the aging of stored units of packed red blood cells (pRBCs) and subsequent lung inflammation after transfusion. Summary Background Data: Large volume pRBC transfusions are associated with multiple adverse clinical sequelae, including lung inflammation. Microparticles are formed in stored pRBCs over time and have been shown to contribute to lung inflammation after transfusion. Methods: Human and murine pRBCs were stored with or without amitriptyline, a functional inhibitor of acid sphingomyelinase, or obtained from acid sphingomyelinase-deficient mice, and lung inflammation was studied in mice receiving transfusions of pRBCs and microparticles isolated from these units. Results: Acid sphingomyelinase activity in pRBCs was associated with the formation of ceramide and the release of microparticles. Treatment of pRBCs with amitriptyline inhibited acid sphingomyelinase activity, ceramide accumulation, and microparticle production during pRBC storage. Transfusion of aged pRBCs or microparticles isolated from aged blood into mice caused lung inflammation. This was attenuated after transfusion of pRBCs treated with amitriptyline or from acid sphingomyelinase-deficient mice. Conclusions: Acid sphingomyelinase inhibition in stored pRBCs offers a novel mechanism for improving the quality of stored blood.},
  language  = {en}
}
@article{GereckeEdlichGiulbudagianetal.2017,
  author    = {Gerecke, Christian and Edlich, Alexander and Giulbudagian, Michael and Schumacher, Fabian and Zhang, Nan and Said, Andre and Yealland, Guy and Lohan, Silke B. and Neumann, Falko and Meinke, Martina C. and Ma, Nan and Calderon, Marcelo and Hedtrich, Sarah and Schaefer-Korting, Monika and Kleuser, Burkhard},
  title     = {Biocompatibility and characterization of polyglycerol-based thermoresponsive nanogels designed as novel drug-delivery systems and their intracellular localization in keratinocytes},
  series = {Nanotoxicology},
  volume    = {11},
  journal   = {Nanotoxicology},
  publisher = {Routledge, Taylor \& Francis Group},
  address   = {Abingdon},
  issn      = {1743-5390},
  doi       = {10.1080/17435390.2017.1292371},
  pages     = {267 -- 277},
  year      = {2017},
  abstract  = {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.},
  language  = {en}
}
@article{SahleGereckeKleuseretal.2017,
  author    = {Sahle, Fitsum Feleke and Gerecke, Christian and Kleuser, Burkhard and Bodmeier, Roland},
  title     = {Formulation and comparative in vitro evaluation of various dexamethasone-loaded pH-sensitive polymeric nanoparticles intended for dermal applications},
  series = {International Journal of Pharmaceutics},
  volume    = {516},
  journal   = {International Journal of Pharmaceutics},
  number    = {1-2},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0378-5173},
  doi       = {10.1016/j.ijpharm.2016.11.029},
  pages     = {21 -- 31},
  year      = {2017},
  abstract  = {pH-sensitive nanoparticles have a great potential for dermal and transfollicular drug delivery. In this study, pH-sensitive, dexamethasone-loaded Eudragit (R) L 100, Eudragit (R) L 100-55, Eudragit (R) S 100, HPMCP-50, HPMCP-55 and cellulose acetate phthalate nanoparticles were prepared by nanoprecipitation and characterized. The pH-dependent swelling, erosion, dissolution and drug release kinetics were investigated in vitro using dynamic light scattering and Franz diffusion cells, respectively. Their toxicity potential was assessed by the ROS and MTT assays. 100-700 nm nanoparticles with high drug loading and entrapment efficiency were obtained. The nanoparticles bear no toxicity potential. Cellulose phthalates nanoparticles were more sensitive to pH than acrylates nanoparticles. They dissolved in 10 mM pH 7.5 buffer and released > 80\% of the drug within 7 h. The acrylate nanoparticles dissolved in 40 mM pH 7.5 buffer and released 65-70\% of the drug within 7 h. The nanoparticles remained intact in 10 and 40 mM pH 6.0 buffers (HPMCP nanoparticles dissolved in 40 mM pH 6.0 buffer) and released slowly. The nanoparticles properties could be modulated by blending the different polymers. In conclusion, various pH-sensitive nanoparticles that could release differently on the skin surface and dissolve and release in the hair follicles were obtained.},
  language  = {en}
}
@article{RadbruchPischonOstrowskietal.2017,
  author    = {Radbruch, Moritz and Pischon, Hannah and Ostrowski, Anja and Volz, Pierre and Brodwolf, Robert and Neumann, Falko and Unbehauen, Michael and Kleuser, Burkhard and Haag, Rainer and Ma, Nan and Alexiev, Ulrike and Mundhenk, Lars and Gruber, Achim D.},
  title     = {Dendritic core-multishell nanocarriers in murine models of healthy and atopic skin},
  series = {Nanoscale Research Letters},
  volume    = {12},
  journal   = {Nanoscale Research Letters},
  number    = {64},
  publisher = {Springer},
  address   = {New York},
  issn      = {1556-276X},
  doi       = {10.1186/s11671-017-1835-0},
  pages     = {12},
  year      = {2017},
  abstract  = {Dendritic hPG-amid-C18-mPEG core-multishell nanocarriers (CMS) represent a novel class of unimolecular micelles that hold great potential as drug transporters, e. g., to facilitate topical therapy in skin diseases. Atopic dermatitis is among the most common inflammatory skin disorders with complex barrier alterations which may affect the efficacy of topical treatment. Here, we tested the penetration behavior and identified target structures of unloaded CMS after topical administration in healthy mice and in mice with oxazolone-induced atopic dermatitis. We further examined whole body distribution and possible systemic side effects after simulating high dosage dermal penetration by subcutaneous injection. Following topical administration, CMS accumulated in the stratum corneum without penetration into deeper viable epidermal layers. The same was observed in atopic dermatitis mice, indicating that barrier alterations in atopic dermatitis had no influence on the penetration of CMS. Following subcutaneous injection, CMS were deposited in the regional lymph nodes as well as in liver, spleen, lung, and kidney. However, in vitro toxicity tests, clinical data, and morphometry-assisted histopathological analyses yielded no evidence of any toxic or otherwise adverse local or systemic effects of CMS, nor did they affect the severity or course of atopic dermatitis. Taken together, CMS accumulate in the stratum corneum in both healthy and inflammatory skin and appear to be highly biocompatible in the mouse even under conditions of atopic dermatitis and thus could potentially serve to create a depot for anti-inflammatory drugs in the skin.},
  language  = {en}
}
@misc{DoegeSchumacherBalzusetal.2017,
  author    = {D{\"o}ge, Nadine and Schumacher, Fabian and Balzus, Benjamin and Colombo, Miriam and Hadam, Sabrina and Rancan, Fiorenza and Blume-Peytavi, Ulrike and Kleuser, Burkhard and Bodmeier, Roland and Vogt, Annika},
  title     = {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},
  series = {Journal der Deutschen Dermatologischen Gesellschaft},
  volume    = {15},
  journal   = {Journal der Deutschen Dermatologischen Gesellschaft},
  publisher = {Wiley},
  address   = {Berlin},
  issn      = {1610-0379},
  pages     = {182 -- 182},
  year      = {2017},
  abstract  = {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.},
  language  = {en}
}
@article{BalzusSahleHoenzkeetal.2017,
  author    = {Balzus, Benjamin and Sahle, Fitsum Feleke and H{\"o}nzke, Stefan and Gerecke, Christian and Schumacher, Fabian and Hedtrich, Sarah and Kleuser, Burkhard and Bodmeier, Roland},
  title     = {Formulation and ex vivo evaluation of polymeric nanoparticles for controlled delivery of corticosteroids to the skin and the corneal epithelium},
  series = {European journal of pharmaceutics and biopharmaceutics : EJPB ; official journal of the International Association for Pharmaceutical Technology},
  volume    = {115},
  journal   = {European journal of pharmaceutics and biopharmaceutics : EJPB ; official journal of the International Association for Pharmaceutical Technology},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0939-6411},
  doi       = {10.1016/j.ejpb.2017.02.001},
  pages     = {122 -- 130},
  year      = {2017},
  abstract  = {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.},
  language  = {en}
}
@article{McVeyKimTabuchietal.2017,
  author    = {McVey, Mark J. and Kim, Michael and Tabuchi, Arata and Srbely, Victoria and Japtok, Lukasz and Arenz, Christoph and Rotstein, Ori and Kleuser, Burkhard and Semple, John W. and Kuebler, Wolfgang M.},
  title     = {Acid sphingomyelinase mediates murine acute lung injury following transfusion of aged platelets},
  series = {American journal of physiology : Lung cellular and molecular physiology},
  volume    = {312},
  journal   = {American journal of physiology : Lung cellular and molecular physiology},
  number    = {5},
  publisher = {American Physiological Society},
  address   = {Bethesda},
  issn      = {1040-0605},
  doi       = {10.1152/ajplung.00317.2016},
  pages     = {625 -- 637},
  year      = {2017},
  abstract  = {Pulmonary complications from stored blood products are the leading cause of mortality related to transfusion. Transfusion-related acute lung injury is mediated by antibodies or bioactive mediators, yet underlying mechanisms are incompletely understood. Sphingolipids such as ceramide regulate lung injury, and their composition changes as a function of time in stored blood. Here, we tested the hypothesis that aged platelets may induce lung injury via a sphingolipid-mediated mechanism. To assess this hypothesis, a two-hit mouse model was devised. Recipient mice were treated with 2 mg/kg intraperitoneal lipopolysaccharide (priming) 2 h before transfusion of 10 ml/kg stored (1-5 days) platelets treated with or without addition of acid sphingomyelinase inhibitor ARC39 or platelets from acid sphingomyelinase-deficient mice, which both reduce ceramide formation. Transfused mice were examined for signs of pulmonary neutrophil accumulation, endothelial barrier dysfunction, and histological evidence of lung injury. Sphingolipid profiles in stored platelets were analyzed by mass spectrophotometry. Transfusion of aged platelets into primed mice induced characteristic features of lung injury, which increased in severity as a function of storage time. Ceramide accumulated in platelets during storage, but this was attenuated by ARC39 or in acid sphingomyelinase-deficient platelets. Compared with wild-type platelets, transfusion of ARC39-treated or acid sphingomyelinase-deficient aged platelets alleviated lung injury. Aged platelets elicit lung injury in primed recipient mice, which can be alleviated by pharmacological inhibition or genetic deletion of acid sphingomyelinase. Interventions targeting sphingolipid formation represent a promising strategy to increase the safety and longevity of stored blood products.},
  language  = {en}
}
@article{FolkessonVorkapicGulbinsetal.2017,
  author    = {Folkesson, Maggie and Vorkapic, Emina and Gulbins, Erich and Japtok, Lukasz and Kleuser, Burkhard and Welander, Martin and L{\"a}nne, Toste and W{\aa}gs{\"a}ter, Dick},
  title     = {Inflammatory cells, ceramides, and expression of proteases in perivascular adipose tissue adjacent to human abdominal aortic aneurysms},
  series = {Journal of vascular surgery},
  volume    = {65},
  journal   = {Journal of vascular surgery},
  number    = {4},
  publisher = {Elsevier},
  address   = {New York},
  issn      = {0741-5214},
  doi       = {10.1016/j.jvs.2015.12.056},
  pages     = {1171 -- 1179},
  year      = {2017},
  abstract  = {Background: Abdominal aortic aneurysm (AAA) is a deadly irreversible weakening and distension of the abdominal aortic wall. The pathogenesis of AAA remains poorly understood. Investigation into the physical and molecular characteristics of perivascular adipose tissue (PVAT) adjacent to AAA has not been done before and is the purpose of this study. Methods and Results: Human aortae, periaortic PVAT, and fat surrounding peripheral arteries were collected from patients undergoing elective surgical repair of AAA. Control aortas were obtained from recently deceased healthy organ donors with no known arterial disease. Aorta and PVAT was found in AAA to larger extent compared with control aortas. Immunohistochemistry revealed neutrophils, macrophages, mast cells, and T-cells surrounding necrotic adipocytes. Gene expression analysis showed that neutrophils, mast cells, and T-cells were found to be increased in PVAT compared with AAA as well as cathepsin K and S. The concentration of ceramides in PVAT was determined using mass spectrometry and correlated with content of T-cells in the PVAT. Conclusions: Our results suggest a role for abnormal necrotic, inflamed, proteolytic adipose tissue to the adjacent aneurysmal aortic wall in ongoing vascular damage.},
  language  = {en}
}
@misc{HalibasicFuerstHeidenetal.2017,
  author    = {Halibasic, Emina and Fuerst, Elisabeth and Heiden, Denis and Japtok, Lukasz and Diesner, Susanne C. and Hillebrand, P. and Trauner, Michael and Kleuser, Burkhard and Kazemi-Shirazi, Lili and Untersmayr, Eva},
  title     = {Significantly reduced plasma levels of the bioactive sphingolipid S1P in lung transplanted cystic fibrosis patients are associated with gastrointestinal symptoms},
  series = {Allergy},
  volume    = {72},
  journal   = {Allergy},
  number    = {S103},
  publisher = {Wiley},
  address   = {Hoboken},
  issn      = {0105-4538},
  pages     = {195 -- 195},
  year      = {2017},
  language  = {en}
}
@article{ZhangSaidWischkeetal.2017,
  author    = {Zhang, Nan and Said, Andre and Wischke, Christian and Kral, Vivian and Brodwolf, Robert and Volz, Pierre and Boreham, Alexander and Gerecke, Christian and Li, Wenzhong and Neffe, Axel T. and Kleuser, Burkhard and Alexiev, Ulrike and Lendlein, Andreas and Sch{\"a}fer-Korting, Monika},
  title     = {Poly[acrylonitrile-co-(N-vinyl pyrrolidone)] nanoparticles - Composition-dependent skin penetration enhancement of a dye probe and biocompatibility},
  series = {European Journal of Pharmaceutics and Biopharmaceutics},
  volume    = {116},
  journal   = {European Journal of Pharmaceutics and Biopharmaceutics},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0939-6411},
  doi       = {10.1016/j.ejpb.2016.10.019},
  pages     = {66 -- 75},
  year      = {2017},
  abstract  = {Nanoparticles can improve topical drug delivery: size, surface properties and flexibility of polymer nanoparticles are defining its interaction with the skin. Only few studies have explored skin penetration for one series of structurally related polymer particles with systematic alteration of material composition. Here, a series of rigid poly[acrylonitrile-co-(N-vinyl pyrrolidone)] model nanoparticles stably loaded with Nile Red or Rhodamin B, respectively, was comprehensively studied for biocompatibility and functionality. Surface properties were altered by varying the molar content of hydrophilic NVP from 0 to 24.1\% and particle size ranged from 35 to 244 nm. Whereas irritancy and genotoxicity were not revealed, lipophilic and hydrophilic nanoparticles taken up by keratinocytes affected cell viability. Skin absorption of the particles into viable skin ex vivo was studied using Nile Red as fluorescent probe. Whilst an intact stratum corneum efficiently prevented penetration, almost complete removal of the horny layer allowed nanoparticles of smaller size and hydrophilic particles to penetrate into viable epidermis and dermis. Hence, systematic variations of nanoparticle properties allows gaining insights into critical criteria for biocompatibility and functionality of novel nanocarriers for topical drug delivery and risks associated with environmental exposure.},
  language  = {en}
}
@misc{PischonRadbruchOstrowskietal.2017,
  author    = {Pischon, Hannah and Radbruch, Moritz and Ostrowski, Anja and Schumacher, Fabian and Hoenzke, Stefan and Kleuser, Burkhard and Hedtrich, Sarah and Fluhr, Joachim W. and Gruber, Achim D. and Mundhenk, Lars},
  title     = {How Effective Is Tacrolimus in the Imiquimod},
  series = {The journal of investigative dermatology},
  volume    = {138},
  journal   = {The journal of investigative dermatology},
  number    = {2},
  publisher = {Elsevier},
  address   = {New York},
  issn      = {0022-202X},
  doi       = {10.1016/j.jid.2017.09.019},
  pages     = {455 -- 458},
  year      = {2017},
  language  = {en}
}
@article{KakkasserySkosyrskiLuethetal.2017,
  author    = {Kakkassery, Vinodh and Skosyrski, S. and L{\"u}th, A. and Kleuser, Burkhard and van der Giet, Maria and Tate, R. and Reinhard, J. and Faissner, Andreas and Joachim, Stephanie Christine and Kociok, N.},
  title     = {Etoposide Upregulates Survival Favoring Sphingosine-1-Phosphate in Etoposide-Resistant Retinoblastoma Cells},
  series = {Pathology \& Oncology Research},
  volume    = {25},
  journal   = {Pathology \& Oncology Research},
  number    = {1},
  publisher = {Springer},
  address   = {Dordrecht},
  issn      = {1219-4956},
  doi       = {10.1007/s12253-017-0360-x},
  pages     = {391 -- 399},
  year      = {2017},
  abstract  = {Improved knowledge of retinoblastoma chemotherapy resistance is needed to raise treatment efficiency. The objective of this study was to test whether etoposide alters glucosyl-ceramide, ceramide, sphingosine, and sphingosine-1-phosphate (sphingosine-1-P) levels in parental retinoblastoma cells (WERI Rb1) or their etoposide-resistant subclones (WERI EtoR). WERI Rb1 and WERI EtoR were incubated with 400 ng/ml etoposide for 24 h. Levels of glucosyl-ceramides, ceramides, sphingosine, sphingosine-1-P were detected by Q-TOF mass spectrometry. Statistical analysis was done by ANOVA followed by Tukey post-hoc test (p < 0.05). The mRNA expression of sphingolipid pathways enzymes in WERI Rb1, WERI EtoR and four human retinoblastoma tissue samples was analyzed by quantitative real-time PCR. Pathways enzymes mRNA expression confirmed similarities of human sphingolipid metabolism in both cell lines and tissue samples, but different relative expression. Significant up-regulation of sphingosine was seen in both cell lines (p < 0.001). Only sphingosine-1-P up-regulation was significantly increased in WERI EtoR (p < 0.01), but not in WERI Rb1 (p > 0.2). Both cell lines upregulate pro-apoptotic sphingosine after etoposide incubation, but only WERI EtoR produces additional survival favorable sphingosine-1-P. These data may suggest a role of sphingosine-1-P in retinoblastoma chemotherapy resistance, although this seems not to be the only resistance mechanism.},
  language  = {en}
}
@misc{Kleuser2017,
  author    = {Kleuser, Burkhard},
  title     = {Medikamentennebenwirkungen auf Haut und Schleimhaut - allergische oder pharmakologisch erkl{\"a}rbare Reaktionen},
  series = {Allergologie},
  volume    = {40},
  journal   = {Allergologie},
  number    = {10},
  publisher = {Dustri-Verlag},
  address   = {Deisenhofen-M{\"u}nchen},
  issn      = {0344-5062},
  pages     = {420 -- 421},
  year      = {2017},
  language  = {de}
}
@article{KachlerBailerHeimetal.2017,
  author    = {Kachler, Katerina and Bailer, Maximilian and Heim, Lisanne and Schumacher, Fabian and Reichel, Martin and Holzinger, Corinna D. and Trump, Sonja and Mittler, Susanne and Monti, Juliana and Trufa, Denis I. and Rieker, Ralf J. and Hartmann, Arndt and Sirbu, Horia and Kleuser, Burkhard and Kornhuber, Johannes and Finotto, Susetta},
  title     = {Enhanced acid sphingomyelinase activity drives immune evasion and tumor growth in non-small cell lung carcinoma},
  series = {Cancer research},
  volume    = {77},
  journal   = {Cancer research},
  number    = {21},
  publisher = {American Association for Cancer Research},
  address   = {Philadelphia},
  issn      = {0008-5472},
  doi       = {10.1158/0008-5472.CAN-16-3313},
  pages     = {5963 -- 5976},
  year      = {2017},
  abstract  = {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.},
  language  = {en}
}
@article{WallmeyerDietertSochorovaetal.2017,
  author    = {Wallmeyer, Leonie and Dietert, Kristina and Sochorova, Michaela and Gruber, Achim D. and Kleuser, Burkhard and Vavrova, Katerina and Hedtrich, Sarah},
  title     = {TSLP is a direct trigger for T cell migration in filaggrin-deficient skin equivalents},
  series = {Scientific reports},
  volume    = {7},
  journal   = {Scientific reports},
  publisher = {Nature Publ. Group},
  address   = {London},
  issn      = {2045-2322},
  doi       = {10.1038/s41598-017-00670-2},
  pages     = {12},
  year      = {2017},
  abstract  = {Mutations in the gene encoding for filaggrin (FLG) are major predisposing factors for atopic dermatitis (AD). Besides genetic predisposition, immunological dysregulations considerably contribute to its pathophysiology. For example, thymic stromal lymphopoietin (TSLP) is highly expressed in lesional atopic skin and significantly contributes to the pathogenesis of AD by activating dendritic cells that then initiate downstream effects on, for example, T cells. However, little is known about the direct interplay between TSLP, filaggrin-deficient skin and other immune cells such as T lymphocytes. In the present study, FLG knockdown skin equivalents, characterised by intrinsically high TSLP levels, were exposed to activated CD4(+) T cells. T cell exposure resulted in an inflammatory phenotype of the skin equivalents. Furthermore, a distinct shift from a Th1/Th17 to a Th2/Th22 profile was observed following exposure of T cells to filaggrin-deficient skin equivalents. Interestingly, TSLP directly stimulated T cell migration exclusively in filaggrin-deficient skin equivalents even in the absence of dendritic cells, indicating a hitherto unknown role of TSLP in the pathogenesis of AD.},
  language  = {en}
}
@article{SpeckmannSchulzHilleretal.2017,
  author    = {Speckmann, Bodo and Schulz, Sarah and Hiller, Franziska and Hesse, Deike and Schumacher, Fabian and Kleuser, Burkhard and Geisel, Juergen and Obeid, Rima and Grune, Tilman and Kipp, Anna Patricia},
  title     = {Selenium increases hepatic DNA methylation and modulates one-carbon metabolism in the liver of mice},
  series = {The journal of nutritional biochemistry},
  volume    = {48},
  journal   = {The journal of nutritional biochemistry},
  publisher = {Elsevier},
  address   = {New York},
  issn      = {0955-2863},
  doi       = {10.1016/j.jnutbio.2017.07.002},
  pages     = {112 -- 119},
  year      = {2017},
  abstract  = {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.},
  language  = {en}
}
@misc{RadbruchPischonOstrowskietal.2017,
  author    = {Radbruch, Moritz and Pischon, Hannah and Ostrowski, Anja and Volz, Pierre and Brodwolf, Robert and Neumann, Falko and Unbehauen, Michael and Kleuser, Burkhard and Haag, Rainer and Ma, Nan and Alexiev, Ulrike and Mundhenk, Lars and Gruber, Achim D.},
  title     = {Dendritic core-multishell nanocarriers in murine models of healthy and atopic skin},
  series = {Postprints der Universit{\"a}t Potsdam Mathematisch-Naturwissenschaftliche Reihe},
  journal   = {Postprints der Universit{\"a}t Potsdam Mathematisch-Naturwissenschaftliche Reihe},
  number    = {724},
  issn      = {1866-8372},
  doi       = {10.25932/publishup-43013},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-430136},
  pages     = {12},
  year      = {2017},
  abstract  = {Dendritic hPG-amid-C18-mPEG core-multishell nanocarriers (CMS) represent a novel class of unimolecular micelles that hold great potential as drug transporters, e. g., to facilitate topical therapy in skin diseases. Atopic dermatitis is among the most common inflammatory skin disorders with complex barrier alterations which may affect the efficacy of topical treatment. Here, we tested the penetration behavior and identified target structures of unloaded CMS after topical administration in healthy mice and in mice with oxazolone-induced atopic dermatitis. We further examined whole body distribution and possible systemic side effects after simulating high dosage dermal penetration by subcutaneous injection. Following topical administration, CMS accumulated in the stratum corneum without penetration into deeper viable epidermal layers. The same was observed in atopic dermatitis mice, indicating that barrier alterations in atopic dermatitis had no influence on the penetration of CMS. Following subcutaneous injection, CMS were deposited in the regional lymph nodes as well as in liver, spleen, lung, and kidney. However, in vitro toxicity tests, clinical data, and morphometry-assisted histopathological analyses yielded no evidence of any toxic or otherwise adverse local or systemic effects of CMS, nor did they affect the severity or course of atopic dermatitis. Taken together, CMS accumulate in the stratum corneum in both healthy and inflammatory skin and appear to be highly biocompatible in the mouse even under conditions of atopic dermatitis and thus could potentially serve to create a depot for anti-inflammatory drugs in the skin.},
  language  = {en}
}