@article{KraftBenzAustinatetal.2010,
  author    = {Kraft, Peter and Benz, Peter Michael and Austinat, Madeleine and Brede, Marc Elmar and Schuh, Kai and Walter, Ulrich and Stoll, Guido and Kleinschnitz, Christoph},
  title     = {Deficiency of Vasodilator-Stimulated Phosphoprotein (VASP) Increases Blood-Brain-Barrier Damage and Edema Formation after Ischemic Stroke in Mice},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-68522},
  year      = {2010},
  abstract  = {Background: Stroke-induced brain edema formation is a frequent cause of secondary infarct growth and deterioration of neurological function. The molecular mechanisms underlying edema formation after stroke are largely unknown. Vasodilator-stimulated phosphoprotein (VASP) is an important regulator of actin dynamics and stabilizes endothelial barriers through interaction with cell-cell contacts and focal adhesion sites. Hypoxia has been shown to foster vascular leakage by downregulation of VASP in vitro but the significance of VASP for regulating vascular permeability in the hypoxic brain in vivo awaits clarification. Methodology/Principal Findings: Focal cerebral ischemia was induced in Vasp2/2 mice and wild-type (WT) littermates by transient middle cerebral artery occlusion (tMCAO). Evan's Blue tracer was applied to visualize the extent of blood-brainbarrier (BBB) damage. Brain edema formation and infarct volumes were calculated from 2,3,5-triphenyltetrazolium chloride (TTC)-stained brain slices. Both mouse groups were carefully controlled for anatomical and physiological parameters relevant for edema formation and stroke outcome. BBB damage (p,0.05) and edema volumes (1.7 mm360.5 mm3 versus 0.8 mm360.4 mm3; p,0.0001) were significantly enhanced in Vasp2/2 mice compared to controls on day 1 after tMCAO. This was accompanied by a significant increase in infarct size (56.1 mm3617.3 mm3 versus 39.3 mm3610.7 mm3, respectively; p,0.01) and a non significant trend (p.0.05) towards worse neurological outcomes. Conclusion: Our study identifies VASP as critical regulator of BBB maintenance during acute ischemic stroke. Therapeutic modulation of VASP or VASP-dependent signalling pathways could become a novel strategy to combat excessive edema formation in ischemic brain damage.},
  subject      = {Vasodilatator-stimuliertes Phosphoprotein},
  language  = {en}
}
@article{FrantzKlaiberBabaetal.2013,
  author    = {Frantz, Stefan and Klaiber, Michael and Baba, Hideo A. and Oberwinkler, Heinz and V{\"o}lker, Katharina and Gaßner, Birgit and Bayer, Barbara and Abeßer, Marco and Schuh, Kai and Feil, Robert and Hofmann, Franz and Kuhn, Michaela},
  title     = {Stress-dependent dilated cardiomyopathy in mice with cardiomyocyte-restricted inactivation of cyclic GMP-dependent protein kinase I},
  series = {European Heart Journal},
  volume    = {34},
  journal   = {European Heart Journal},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-134693},
  pages     = {1233-1244},
  year      = {2013},
  abstract  = {Aims: Cardiac hypertrophy is a common and often lethal complication of arterial hypertension. Elevation of myocyte cyclic GMP levels by local actions of endogenous atrial natriuretic peptide (ANP) and C-type natriuretic peptide (CNP) or by pharmacological inhibition of phosphodiesterase-5 was shown to counter-regulate pathological hypertrophy. It was suggested that cGMP-dependent protein kinase I (cGKI) mediates this protective effect, although the role in vivo is under debate. Here, we investigated whether cGKI modulates myocyte growth and/or function in the intact organism. Methods and results: To circumvent the systemic phenotype associated with germline ablation of cGKI, we inactivated the murine cGKI gene selectively in cardiomyocytes by Cre/loxP-mediated recombination. Mice with cardiomyocyte-restricted cGKI deletion exhibited unaltered cardiac morphology and function under resting conditions. Also, cardiac hypertrophic and contractile responses to β-adrenoreceptor stimulation by isoprenaline (at 40 mg/kg/day during 1 week) were unaltered. However, angiotensin II (Ang II, at 1000 ng/kg/min for 2 weeks) or transverse aortic constriction (for 3 weeks) provoked dilated cardiomyopathy with marked deterioration of cardiac function. This was accompanied by diminished expression of the \([Ca^{2+}]_i\)-regulating proteins SERCA2a and phospholamban (PLB) and a reduction in PLB phosphorylation at Ser16, the specific target site for cGKI, resulting in altered myocyte \(Ca^{2+}_i\) homeostasis. In isolated adult myocytes, CNP, but not ANP, stimulated PLB phosphorylation, \(Ca^{2+}_i\)-handling, and contractility via cGKI. Conclusion: These results indicate that the loss of cGKI in cardiac myocytes compromises the hypertrophic program to pathological stimulation, rendering the heart more susceptible to dysfunction. In particular, cGKI mediates stimulatory effects of CNP on myocyte \(Ca^{2+}_i\) handling and contractility.},
  language  = {en}
}
@article{KorbTngMilenkovicetal.2013,
  author    = {Korb, Doreen and Tng, Priscilla Y. and Milenkovic, Vladimir M. and Reichhart, Nadine and Strauss, Olaf and Ritter, Oliver and Fischer, Tobias and Benz, Peter M. and Schuh, Kai},
  title     = {Identification of PDZ domain containing proteins interacting with \(Ca_v1.2\) and PMCA4b},
  series = {ISRN Cell Biology},
  journal   = {ISRN Cell Biology},
  number    = {Article ID 265182},
  doi       = {10.1155/2013/265182},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-130585},
  pages     = {16},
  year      = {2013},
  abstract  = {PDZ (PSD-95/Disc large/Zonula occludens-1) protein interaction domains bind to cytoplasmic protein C-termini of transmembrane proteins. In order to identify new interaction partners of the voltage-gated L-type \(Ca^{2+}\) channel Cav1.2 and the plasma membrane \(Ca^{2+}\) ATPase 4b (PMCA4b), we used PDZ domain arrays probing for 124 PDZ domains. We confirmed this byGST pulldowns and immunoprecipitations. In PDZ arrays, strongest interactionswith \(Ca_v1.2\) and PMCA4b were found for the PDZ domains of SAP-102, MAST-205, MAGI-1, MAGI-2, MAGI-3, and ZO-1. We observed binding of the \(Ca_v1.2\) C-terminus to PDZ domains of NHERF1/2, Mint-2, and CASK. PMCA4b was observed to interact with Mint-2 and its known interactions with Chapsyn-110 and CASK were confirmed. Furthermore, we validated interaction of \(Ca_v1.2\) and PMCA4b with NHERF1/2, CASK,MAST-205 and MAGI-3 viaimmunoprecipitation. We also verified the interaction of \(Ca_v1.2\) and nNOS and hypothesized that nNOS overexpression might reduce \(Ca^{2+}\) influx through \(Ca_v1.2\). To address this, we measured \(Ca^{2+}\) currents in HEK 293 cells co-expressing \(Ca_v1.2\) and nNOS and observed reduced voltage-dependent \(Ca_v1.2\) activation. Taken together, we conclude that \(Ca_v1.2\) and PMCA4b bind promiscuously to various PDZ domains, and that our data provides the basis for further investigation of the physiological consequences of these interactions.},
  language  = {en}
}
@article{BenzMerkelOffneretal.2013,
  author    = {Benz, Peter M. and Merkel, Carla J. and Offner, Kristin and Abeßer, Marco and Ullrich, Melanie and Fischer, Tobias and Bayer, Barbara and Wagner, Helga and Gambaryan, Stepan and Ursitti, Jeanine A. and Adham, Ibrahim M. and Linke, Wolfgang A. and Feller, Stephan M. and Fleming, Ingrid and Renn{\´e}, Thomas and Frantz, Stefan and Unger, Andreas and Schuh, Kai},
  title     = {Mena/VASP and alphaII-Spectrin complexes regulate cytoplasmic actin networks in cardiomyocytes and protect from conduction abnormalities and dilated cardiomyopathy},
  series = {Cell Communication and Signaling},
  volume    = {11},
  journal   = {Cell Communication and Signaling},
  number    = {56},
  doi       = {10.1186/1478-811X-11-56},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-128760},
  year      = {2013},
  abstract  = {Background: In the heart, cytoplasmic actin networks are thought to have important roles in mechanical support, myofibrillogenesis, and ion channel function. However, subcellular localization of cytoplasmic actin isoforms and proteins involved in the modulation of the cytoplasmic actin networks are elusive. Mena and VASP are important regulators of actin dynamics. Due to the lethal phenotype of mice with combined deficiency in Mena and VASP, however, distinct cardiac roles of the proteins remain speculative. In the present study, we analyzed the physiological functions of Mena and VASP in the heart and also investigated the role of the proteins in the organization of cytoplasmic actin networks. Results: We generated a mouse model, which simultaneously lacks Mena and VASP in the heart. Mena/VASP double-deficiency induced dilated cardiomyopathy and conduction abnormalities. In wild-type mice, Mena and VASP specifically interacted with a distinct αII-Spectrin splice variant (SH3i), which is in cardiomyocytes exclusively localized at Z- and intercalated discs. At Z- and intercalated discs, Mena and β-actin localized to the edges of the sarcomeres, where the thin filaments are anchored. In Mena/VASP double-deficient mice, β-actin networks were disrupted and the integrity of Z- and intercalated discs was markedly impaired. Conclusions: Together, our data suggest that Mena, VASP, and αII-Spectrin assemble cardiac multi-protein complexes, which regulate cytoplasmic actin networks. Conversely, Mena/VASP deficiency results in disrupted β-actin assembly, Z- and intercalated disc malformation, and induces dilated cardiomyopathy and conduction abnormalities.},
  language  = {en}
}
@phdthesis{Schuh2001,
  author    = {Schuh, Kai},
  title     = {Erzeugung und Analyse NF-ATp-defizienter M{\"a}use},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-117},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2001},
  abstract  = {Ziel dieser Arbeit war es, NF-AT1-Gen-defiziente Mauslinien zu erzeugen und die Folgen dieser genetischen Manipulation in vivo zu untersuchen. Die Untersuchung sollte die durch die Gendefizienz erwarteten M{\"a}ngel w{\"a}hrend der Entwicklung (Embryogenese) und, im Besonderen, die Auswirkungen auf das Immunsytem und die Entwicklung und Differenzierung der T-Zellen aufzeigen. Zur Untersuchung der genomischen Organisation des Maus-NF-AT1-Gens wurde eine genomische l-Phagen-DNA-Bibliothek "gescreent" (durchgef{\"u}hrt von Dr. E. Jankevics, Universit{\"a}t von Riga, Lettland), die entsprechenden l-Phagen, die das NF-AT1-Gen enthielten, isoliert und die DNA pr{\"a}pariert. Nach Analyse der klonierten Phagen (Subklonierung und Sequenzierung) wurde eine Restriktionskarte der entsprechenden Bereiche erstellt und der "targeting-vector" erstellt. Der "targeting-vector" wurde durch Elektroporation in embryonale Stammzellen (ES-Zellen) eingebracht und die Integration in das Genom ("Homologe Rekombination") durch Southern Blotting- bzw. PCR-Analyse untersucht. Manipulierte ES-Zellklone wurden in C57Bl/6-Blastozysten injiziert, diese in scheinschwangere Ammentiere transferiert und die Nachkommen nach Geburt anhand der Fellfarben klassifiziert. Nachkommen mit einem hohen Anteil hellen Fells wurden mit C57 Bl/6-Tieren verpaart und die Integration des manipulierten Zellklons in die Keimbahn wurde anhand der wildtypischen Fellfarbe und Genotypisierung nachgewiesen. Bez{\"u}glich des manipulierten NF-ATp-Gens heterozygote F1-Tiere wurden miteinander verpaart, um eine homozygote NF-ATp-defiziente M{\"a}use zu erhalten. Die Deletion des NF-ATp-Proteins wurde durch in Western-Blotting-Experimenten und EMSAs ("electrophoretic mobility shift assays") nachgewiesen. Die NF-ATp-/--Tiere zeigten keine augenscheinlichen Ver{\"a}nderungen w{\"a}hrend der Entwicklung und, bei jungen Tieren, keine offensichtlichen Ver{\"a}nderungen bei der Entwicklung des Immunsystems. In {\"a}lteren Tieren (> 6 Wochen) war eine Hyperproliferation der Zellen des Immunsystems zu beobachten, was mit einer Splenomegalie, einer verst{\"a}rkten Bildung von Keimzentren in lymphatischen Organen, vergr{\"o}ßerten Lymphknoten und einer verlangsamten Involution des Thymus einherging. Weitergehende Untersuchungen der Ursache dieser hyperproliferativen Erkrankung offenbarten eine verminderte klonale Deletion nach Aktivierung. Die Ursachen dieses {\"u}berraschenden Effekts sind wahrscheinlich vielf{\"a}ltig, da NF-AT-Faktoren an der Regulation der Expression vieler Gene beteiligt sind, u.a. des Apoptose-assoziierten CD95-Liganden. Da sich bez{\"u}glich der IL-2-Expression keine Unterschiede zwischen NF-ATp-defizienten Tieren und Kontrollen zeigten, jedoch eine erh{\"o}hte IL-2-Konzentration im Medium kultivierter NF-ATp-defizienter T-Zellen beobachtet wurde, wurde die Bindung von NF-ATp an putative NF-AT-Bindungssequenzen des CD25-Promotors, die transkriptionelle Aktivierung des Promotors mittels Luciferase-Assays und die Expression der IL-2R-alpha-Kette (CD25) untersucht. Es konnte gezeigt werden, daß (1.) NF-ATp an zwei Regionen des CD25-Promotors bindet, (2.) der CD25-Promotor durch NF-ATp transkriptionell stark stimuliert wird und (3.) T-Zellen NF-ATp-defizienter Tiere nach Stimulation eine verminderte CD25-Expression zeigen. In NF-ATp-defizienten Tieren war die Expression von CD25 moderat reduziert, was eine Erkl{\"a}rung f{\"u}r den abgeschw{\"a}chten Ph{\"a}notyp dieser Tiere - im Vergleich zu IL-2- oder CD25-defizienten Tieren - sein kann. Die hyperproliferativen Erkrankungen dieser verschiedenen Mauslinien weisen auf eine Beteiligung der NF-AT-/IL-2-/IL-2R-Signalwege nicht nur w{\"a}hrend der T-Zell-Aktivierung hin, sondern auch auf eine Beteiligung an Signalwegen, die zur anschließenden Inaktivierung und Apoptose der T-Lymphozyten n{\"o}tig sind.},
  subject      = {Maus},
  language  = {de}
}
@article{PoppSchmittBoehrerLangeretal.2021,
  author    = {Popp, Sandy and Schmitt-B{\"o}hrer, Angelika and Langer, Simon and Hofmann, Ulrich and Hommers, Leif and Schuh, Kai and Frantz, Stefan and Lesch, Klaus-Peter and Frey, Anna},
  title     = {5-HTT Deficiency in Male Mice Affects Healing and Behavior after Myocardial Infarction},
  series = {Journal of Clinical Medicine},
  volume    = {10},
  journal   = {Journal of Clinical Medicine},
  number    = {14},
  issn      = {2077-0383},
  doi       = {10.3390/jcm10143104},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-242739},
  year      = {2021},
  abstract  = {Anxiety disorders and depression are common comorbidities in cardiac patients. Mice lacking the serotonin transporter (5-HTT) exhibit increased anxiety-like behavior. However, the role of 5-HTT deficiency on cardiac aging, and on healing and remodeling processes after myocardial infarction (MI), remains unclear. Cardiological evaluation of experimentally na{\"i}ve male mice revealed a mild cardiac dysfunction in ≥4-month-old 5-HTT knockout (-/-) animals. Following induction of chronic cardiac dysfunction (CCD) by MI vs. sham operation 5-HTT-/- mice with infarct sizes >30\% experienced 100\% mortality, while 50\% of 5-HTT+/- and 37\% of 5-HTT+/+ animals with large MI survived the 8-week observation period. Surviving (sham and MI < 30\%) 5-HTT-/- mutants displayed reduced exploratory activity and increased anxiety-like behavior in different approach-avoidance tasks. However, CCD failed to provoke a depressive-like behavioral response in either 5-Htt genotype. Mechanistic analyses were performed on mice 3 days post-MI. Electrocardiography, histology and FACS of inflammatory cells revealed no abnormalities. However, gene expression of inflammation-related cytokines (TGF-β, TNF-α, IL-6) and MMP-2, a protein involved in the breakdown of extracellular matrix, was significantly increased in 5-HTT-/- mice after MI. This study shows that 5-HTT deficiency leads to age-dependent cardiac dysfunction and disrupted early healing after MI probably due to alterations of inflammatory processes in mice.},
  language  = {en}
}
@article{WernerKojonazarovGassneretal.2016,
  author    = {Werner, Franziska and Kojonazarov, Baktybek and Gaßner, Birgit and Abeßer, Marco and Schuh, Kai and V{\"o}lker, Katharina and Baba, Hideo A. and Dahal, Bhola K. and Schermuly, Ralph T. and Kuhn, Michaela},
  title     = {Endothelial actions of atrial natriuretic peptide prevent pulmonary hypertension in mice},
  series = {Basic Research in Cardiology},
  volume    = {111},
  journal   = {Basic Research in Cardiology},
  number    = {2},
  doi       = {10.1007/s00395-016-0541-x},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-190664},
  pages     = {16},
  year      = {2016},
  abstract  = {The cardiac hormone atrial natriuretic peptide (ANP) regulates systemic and pulmonary arterial blood pressure by activation of its cyclic GMP-producing guanylyl cyclase-A (GC-A) receptor. In the lung, these hypotensive effects were mainly attributed to smooth muscle-mediated vasodilatation. It is unknown whether pulmonary endothelial cells participate in the homeostatic actions of ANP. Therefore, we analyzed GC-A/cGMP signalling in lung endothelial cells and the cause and functional impact of lung endothelial GC-A dysfunction. Western blot and cGMP determinations showed that cultured human and murine pulmonary endothelial cells exhibit prominent GC-A expression and activity which were markedly blunted by hypoxia, a condition known to trigger pulmonary hypertension (PH). To elucidate the consequences of impaired endothelial ANP signalling, we studied mice with genetic endothelial cell-restricted ablation of the GC-A receptor (EC GC-A KO). Notably, EC GC-A KO mice exhibit PH already under resting, normoxic conditions, with enhanced muscularization of small arteries and perivascular infiltration of inflammatory cells. These alterations were aggravated on exposure of mice to chronic hypoxia. Lung endothelial GC-A dysfunction was associated with enhanced expression of angiotensin converting enzyme (ACE) and increased pulmonary levels of Angiotensin II. Angiotensin II/AT(1)-blockade with losartan reversed pulmonary vascular remodelling and perivascular inflammation of EC GC-A KO mice, and prevented their increment by chronic hypoxia. This experimental study indicates that endothelial effects of ANP are critical to prevent pulmonary vascular remodelling and PH. Chronic endothelial ANP/GC-A dysfunction, e.g. provoked by hypoxia, is associated with activation of the ACE-angiotensin pathway in the lung and PH.},
  language  = {en}
}
@article{HepbasliGredyUllrichetal.2021,
  author    = {Hepbasli, Denis and Gredy, Sina and Ullrich, Melanie and Reigl, Amelie and Abeßer, Marco and Raabe, Thomas and Schuh, Kai},
  title     = {Genotype- and Age-Dependent Differences in Ultrasound Vocalizations of SPRED2 Mutant Mice Revealed by Machine Deep Learning},
  series = {Brain Sciences},
  volume    = {11},
  journal   = {Brain Sciences},
  number    = {10},
  issn      = {2076-3425},
  doi       = {10.3390/brainsci11101365},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-248525},
  year      = {2021},
  abstract  = {Vocalization is an important part of social communication, not only for humans but also for mice. Here, we show in a mouse model that functional deficiency of Sprouty-related EVH1 domain-containing 2 (SPRED2), a protein ubiquitously expressed in the brain, causes differences in social ultrasound vocalizations (USVs), using an uncomplicated and reliable experimental setting of a short meeting of two individuals. SPRED2 mutant mice show an OCD-like behaviour, accompanied by an increased release of stress hormones from the hypothalamic-pituitary-adrenal axis, both factors probably influencing USV usage. To determine genotype-related differences in USV usage, we analyzed call rate, subtype profile, and acoustic parameters (i.e., duration, bandwidth, and mean peak frequency) in young and old SPRED2-KO mice. We recorded USVs of interacting male and female mice, and analyzed the calls with the deep-learning DeepSqueak software, which was trained to recognize and categorize the emitted USVs. Our findings provide the first classification of SPRED2-KO vs. wild-type mouse USVs using neural networks and reveal significant differences in their development and use of calls. Our results show, first, that simple experimental settings in combination with deep learning are successful at identifying genotype-dependent USV usage and, second, that SPRED2 deficiency negatively affects the vocalization usage and social communication of mice.},
  language  = {en}
}