@phdthesis{Hennig2002, author = {Hennig, Thomas}, title = {Regulation von Adenosin- und Glutamatrezeptoren bei M{\"a}usen mit molekularen Defekten des Serotoninsystems}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-5994}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2002}, abstract = {Wir untersuchten die Konzentrationen an Adenosinrezeptoren und Glutamatrezeptoren bei M{\"a}usen mit molekularen Defekten des Serotoninsystems. Dies betraf einerseits den Mangel an Serotonintransportern und andererseits den Mangel an Monoaminoxidase A (MAOA). Dabei verglichen wir M{\"a}use mit einem einzelnen Knockout des entsprechenden Gens mit Doppelknockout-Tieren, denen beide Gene fehlten. Desweiteren untersuchten wir die Ver{\"a}nderung der Konzentration an Glutamatrezeptoren bei alten Tieren mit einem Knockout des Serotonintransporters.}, language = {de} } @phdthesis{Jarczok2006, author = {Jarczok, Tomasz Antoni}, title = {Genetische Einfl{\"u}sse auf topographische elektrophysiologische Korrelate motorischer Inhibition}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-20392}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2006}, abstract = {Go- und NoGo-Centroide und die NoGo-Anteriorisierung (NGA) sind topographische elektrophysiologische Parameter, die w{\"a}hrend eines Continuous Performance Test (CPT) gemessen werden k{\"o}nnen. Es wurde der Einfluss genetischer Varianten auf diese Messgr{\"o}ßen an gesunden Individuen untersucht. Zwei die Funktion des serotonergen Systems modulierende Gene (5-HTTLPR und MAOALPR) beeinflussten die topographischen elektrophysiologischen Parameter nicht. Varianten des Gens Dysbindin (DTNBP1), die mit Schizophrenie in Zusammenhang gebracht werden, waren mit Ver{\"a}nderungen der NGA assoziiert. Die Ergebnisse deuten auf einen m{\"o}glichen Einfluss des Dysbindin-Genotyps auf frontale Gehirnfunktionen.}, language = {de} } @phdthesis{Hampe2006, author = {Hampe, Michael}, title = {Evolutionsgenetische Untersuchung von Genvarianten monoaminerger Systeme bei nichtmenschlichen Primaten}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-19064}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2006}, abstract = {Die Verbindungen zwischen Genvariationen und Verhaltensmerkmalen bzw. psychiatrischen St{\"o}rungen sind in den letzten Jahren in den Blickpunkt vieler Studien gelangt. Auf der Suche nach neuen Polymorphismen bieten sich dem Menschen verwandte Affenarten an. Zeigen sich bei diesen Primaten den Menschen orthologe Polymorphismen, k{\"o}nnten so neue Erkenntnisse {\"u}ber deren evolutionsgenetische Entwicklung und die {\"U}bertragbarkeit auf menschliche Gen-Merkmal-Assoziationen gewonnen werden. Vergleicht man die unterschiedliche Transkriptionsaktivit{\"a}t des Monoaminoxidase A Gens beim Menschen, beeinflussen L{\"a}ngenvariationen innerhalb der repetetiven Sequenz (VNTR) des MAOA Promotors vor allem aggressive und antisoziale Verhaltensmerkmale. Zudem erh{\"o}ht sich das Risiko f{\"u}r psychiatrische St{\"o}rungen. In dieser Arbeit wurde die Anwesenheit und Variabilit{\"a}t der repetetiven Sequenz des MAOA Promotors bei mehreren Arten von nichtmenschlichen Primaten ausgewertet. Bei einigen Affenarten konnten L{\"a}ngenvariationen innerhalb der repetetiven Sequenz (VNTR) gefunden werden. Die Sequenzanalyse dieser Kontrollregion zeigte das Vorkommen von VNTRs in Pan troglodytes, Pan paniscus, Gorilla gorilla, Pongo pygmaeus, Macaca mulatta und Theropithecus gelada. Die Mehrheit von Pan troglodytes und Pan paniscus hatten ein einfaches Repeat mit einer der menschlichen VNTR Sequenz identischen Sequenz. Die VNTR Sequenz von Macaca mulatta zeigte die h{\"a}ufigsten L{\"a}ngenvariationen mit Allel-frequenzen von 35\%, 25\% und 40\% entsprechend den 5-, 6- und 7-Repeatvarianten. Das Ausmaß der Repeatvariationen des MAOA Promotors st{\"u}tzt die Annahme, dass ein Zusammenhang zwischen der Expression von MAOA und aggressiven und antisozialen Verhaltensmerkmalen bei Menschen und auch Rhesusaffen besteht. Neben dem MAOA Promotor wurden auch das Dopamin-Rezeptor-Gen D4 (DRD4), das Dopamin-Transporter-Gen (DAT) und der Promotor des Serotonin-Transporter-Gens (5-HTTLPR) untersucht. Ein Macaca mulatta (NIH Primate Center), der eine XL/L-Bande aufwies, zeigte bei der Sequenzanalyse des Promotors des Serotonin-Transporter-Gens (5-HTTLPR) eine 21 bp große Insertion kurz vor dem Int1- Primer. Sollten sich die Ergebnisse in weiteren Untersuchungen best{\"a}tigen, w{\"a}re dies ein erneuter Hinweis auf die mitbestimmende Rolle von MAOA und 5-HTTLPR und deren Allel-Variationen bei spezifischen menschlichen Charakterz{\"u}gen.}, language = {de} } @phdthesis{Goessler2007, author = {G{\"o}ßler, Michael}, title = {Molekulargenetische Untersuchungen serotonerger Kandidatengene bei Zwangsst{\"o}rungen im Kindes- und Jugendalter}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-23773}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2007}, abstract = {Zwangsst{\"o}rungen, im englischen als Obsessive Compulsive Disorder (OCD) bezeichnet, sind sowohl in der Erwachsenen- als auch in der Kinder- und Jugendpsychiatrie bekannte Krankheitsbilder, die mit einer Lebenszeitpr{\"a}valenz von 2,5 - 3\% zu den h{\"a}ufigsten psychiatrischen Erkrankungen im Kindes- und Jugendalter geh{\"o}ren. Sie stellen in der Regel eine erhebliche Belastung sowohl f{\"u}r die betroffenen Kinder als auch f{\"u}r deren Familie dar und schr{\"a}nken den allt{\"a}glichen Lebensablauf je nach Auspr{\"a}gung erheblich ein. Familien- und Zwillingsuntersuchungen zeigen, dass bei Zwangsst{\"o}rungen eine deutliche famili{\"a}re Belastung vorliegt. Gerade bei einer fr{\"u}hen Manifestation im Kindesalter (auf englisch als early onset bezeichnet) konnten Familienstudien zeigen, dass genetische Faktoren eine besonders ausgepr{\"a}gte Rolle spielen. Diese formalgenetischen Studien legen weitere Untersuchungen auf molekulargenetischer Ebene f{\"u}r Zwangsst{\"o}rungen im Kindes- und Jugendalter nahe. Pharmakologische Studien und erste molekulargenetische Studien verweisen zudem auf einen Zusammenhang zwischen Zwangs- und Angstsymptomen und dem Serotoninstoffwechsel. Selektive Serotonin Wiederaufnahme-Hemmer (Selective Serotonine Reuptake Inhibitors, SSRI) und tricyclische Antidepressiva sind bei der Behandlung von Zwangsst{\"o}rungen besonders wirksam. Auch im Kindes- und Jugendalter sind diese Medikamente aufgrund ihrer positiven Wirkung bei Zwangsst{\"o}rungen Mittel der ersten Wahl. Insgesamt wird die Pathogenese der Zwangsst{\"o}rungen nach aktuellem Forschungsstand als multifaktoriell angenommen. Dabei bezieht sich bisher die {\"u}berwiegende Zahl der Untersuchungen auf Zwangsst{\"o}rungen erwachsener Patienten. Nach aktuellem Kenntnisstand handelt es sich bei der vorliegenden Arbeit um die ersten familienbasierten Assoziationsstudien bei Kindern und Jugendlichen mit Zwangsst{\"o}rungen. Zielsetzung dieser Arbeit war die Untersuchung einer Assoziation von Varianten in ausgew{\"a}hlten Genen des serotonergen Systems und juvenilen Zwangsst{\"o}rungen. Die Auswahl der Kandidatengene f{\"u}r Zwangsst{\"o}rungen erfolgte auf patho-physiologischen {\"U}berlegungen: Die Tryptophanhydroxylase als geschwindigkeits-bestimmendes Enzym in der Synthese von Serotonin, der Serotonin-1B-Rezeptor als Zielorgan mit autoregulierender Funktion auf das serotonerge System, sowie der Serotonintransporter, der, therapeutisch genutzt, von SSRIs blockiert wird. Untersuchungen zu den genannten Kandidatengenen liegen bei erwachsenen Patienten mit Zwangsst{\"o}rungen vor, die Ergebnisse sollten in unserer Studie repliziert werden. 64 Kinder und Jugendliche, sowie deren leibliche Eltern wurden in die Untersuchung eingeschlossen. In den vorliegenden molekulargenetischen Untersuchungen konnten f{\"u}r Varianten im Tryptophanhydroxylase-1-Gen und dem Serotonin-1B-Rezeptor-Gen kein Zusammenhang mit Zwangsst{\"o}rungen bei Kindern und Jugendlichen gesehen werden. Die funktionelle Variante des Serotonintransporter-Gens, die zu einer h{\"o}heren Aktivit{\"a}t des Transporters f{\"u}hrt, wurde tendenziell h{\"a}ufiger bei den Patienten mit Zwangsst{\"o}rungen beobachtet. Der Befund entspricht damit in der Richtung den fr{\"u}heren Befunden von erwachsenen Patienten.}, language = {de} } @phdthesis{Herzog2008, author = {Herzog, Anna Laura}, title = {Migr{\"a}ne und das serotonerge System}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-29380}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2008}, abstract = {Untersuchung zu single-nucleotid-polymorphismen (SNPs) der Serotoninrezeptoren 5-HT2A, 5-HT3A, des Neurotrophins BDNF und des Enzyms Tryptophanhydroxlase auf deren Korrelation mit Migr{\"a}ne mit und ohne Aura.}, subject = {Migr{\"a}ne}, language = {de} } @phdthesis{Eujen2009, author = {Eujen, Andrea}, title = {Serotonerge Gene und NOS1 als Risikofaktoren f{\"u}r gewaltt{\"a}tiges Verhalten}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-36479}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2009}, abstract = {Pers{\"o}nlichkeit im Allgemeinen wird, neben Umwelteinfl{\"u}ssen, durch genetische Komponenten beeinflusst. Bisher konnten jedoch nur wenige funktionelle Genvarianten mit Verhaltensz{\"u}gen assoziiert werden. Aggressives Verhalten als spezifisches Verhaltensmuster wird durch eine Reihe von Genvariationen beeinflusst, die in serotonerge, dopaminerge und nitrinerge Regelkreise eingreifen. Neben der genetischen Komponente pr{\"a}disponieren aber hier ganz erheblich auch {\"a}ußere Faktoren in der Umwelt, wie z.B. das soziale Umfeld, in dem Kinder und Jugendliche aufwachsen, f{\"u}r die Entwicklung von gewaltt{\"a}tigem Verhalten. Ziel der vorliegenden Arbeit war es, einen m{\"o}glichen Einfluss von vier verschiedenen funktionellen Gen-Polymorphismen (MAOA-uVNTR, DAT-uVNTR, NOS1 Ex1f-uVNTR und NOS1 Ex1c-SNP) auf Gewaltt{\"a}tigkeit bzw. Aggressivit{\"a}t zu untersuchen. Außerdem wurden Gen x Umweltinteraktionen im Bezug auf ung{\"u}nstige soziale Bedingungen in der Kindheit untersucht. Eine aus 184 M{\"a}nnern bestehende Stichprobe von Straff{\"a}lligen wurde in eine Gruppe von gewaltt{\"a}tigen und eine Gruppe von nicht-gewaltt{\"a}tigen Straft{\"a}tern unterteilt. Durch die logistische Regressionsanalyse konnte ermittelt werden, dass der MAO-A Genotyp, wie auch ung{\"u}nstige soziale Bedingungen in der Kindheit, unabh{\"a}ngig voneinander f{\"u}r gewaltt{\"a}tiges Verhalten pr{\"a}dispositionieren. 45\% der Gewaltt{\"a}tigen, aber nur 30\% der nicht-gewaltt{\"a}tigen Studienteilnehmer sind Tr{\"a}ger des niedrig-aktiven kurzen MAO-A Allels. Die neuronale Isoform der Stickstoffmonoxid-Synthase (NOS-I) wurde, ebenso wie MAO-A, in Tierversuchen mit aggressiven Verhaltensweisen assoziiert. In der vorliegenden Arbeit konnte gezeigt werden, dass es auch einen Zusammenhang zwischen einem funktionellen Promotorpolymorphismus von NOS1 und menschlicher Aggressivit{\"a}t gibt. Im Gegensatz zu MAOA und NOS1 beeinflusst ein funktioneller Polymorphismus im DAT1-Gen Gewaltt{\"a}tigkeit nicht. Diese Ergebnisse legen komplexe Interaktionen zwischen genetischer Variation und Umweltfaktoren nahe und zeigen gleichzeitig, dass aggressives Verhalten nicht durch einfache Vererbungsmodi zu erkl{\"a}ren ist.}, subject = {Aggression}, language = {de} } @phdthesis{Kriegebaum2009, author = {Kriegebaum, Claudia}, title = {Spatio-temporal Expression Patterns of the Serotonin Synthesis Enzymes TPH1 and TPH2 and Effects of Acute Stress}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-40839}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2009}, abstract = {Several lines of evidence implicate a dysregulation of tryptophan hydroxylase (TPH)-dependent serotonin (5-HT) synthesis in emotions and stress and point to their potential relevance to the etiology and pathogenesis of various neuropsychiatric disorders. However, the differential expression pattern of the two isoforms TPH1 and TPH2 which encode two forms of the rate-limiting enzyme of 5-HT synthesis is controversial. Here, a comprehensive spatio-temporal analysis clarifies TPH1 and TPH2 expression during pre- and postnatal development of the mouse brain and in adult human brain as well as in peripheral organs including the pineal gland. Four different methods (real time PCR, in situ hybridization, immunohistochemistry and Western blot analysis) were performed to systematically control for tissue-, species- and isoform-specific expression on both the pre- and posttranslational level. TPH2 expression was consistently detected in the raphe nuclei, as well as in fibres in the deep pineal gland and in the gastrointestinal tract. Although TPH1 expression was found in these peripheral tissues, no significant TPH1 expression was detected in the brain, neither during murine development, nor in mouse and human adult brain. Also under conditions like stress and clearing the tissue from blood cells, no changes in expression levels were detectable. Furthermore, the reuptake of 5-HT into the presynaptic neuron by the serotonin transporter (SERT) is the major mechanism terminating the neurotransmitter signal. Thus, mice with a deletion in the Sert gene (Sert KO mice) provide an adequate model for human affective disorders to study lifelong modified 5-HT homeostasis in interaction with stressful life events. To further explore the role of TPH isoforms, Tph1 and Tph2 expression was studied in the raphe nuclei of Sert deficient mice under normal conditions as well as following exposure to acute immobilization stress. Interestingly, no statistically significant changes in expression were detected. Moreover, in comparison to Tph2, no relevant Tph1 expression was detected in the brain independent from genotype, gender and treatment confirming expression in data from native animals. Raphe neurons of a brain-specific Tph2 conditional knockout (cKO) model were completely devoid of Tph2-positive neurons and consequently 5-HT in the brain, with no compensatory activation of Tph1 expression. In addition, a time-specific Tph2 inducible (i) KO mouse provides a brain-specific knockdown model during adult life, resulting in a highly reduced number of Tph2-positive cells and 5-HT in the brain. Intriguingly, expression studies detected no obvious alteration in expression of 5-HT system-associated genes in these brain-specific Tph2 knockout and knockdown models. The findings on the one hand confirm the specificity of Tph2 in brain 5-HT synthesis across the lifespan and on the other hand indicate that neither developmental nor adult Tph2-dependent 5-HT synthesis is required for normal formation of the serotonergic system, although Tph1 does not compensate for the lack of 5-HT in the brain of Tph2 KO models. A further aim of this thesis was to investigate the expression of the neuropeptide oxytocin, which is primarily produced in the hypothalamus and released for instance in response to stimulation of 5-HT and selective serotonin reuptake inhibitors (SSRIs). Oxytocin acts as a neuromodulator within the central nervous system (CNS) and is critically involved in mediating pain modulation, anxiolytic-like effects and decrease of stress response, thereby reducing the risk for emotional disorders. In this study, the expression levels of oxytocin in different brain regions of interest (cortex, hippocampus, amygdala, hypothalamus and raphe nuclei) from female and male wildtype (WT) and Sert KO mice with or without exposure to acute immobilization stress were investigated. Results showed significantly higher expression levels of oxytocin in brain regions which are involved in the regulation of emotional stimuli (amygdala and hippocampus) of stressed male WT mice, whereas male Sert KO as well as female WT and Sert KO mice lack these stress-induced changes. These findings are in accordance with the hypothesis of oxytocin being necessary for protection against stress, depressive mood and anxiety but suggest gender-dependent differences. The lack of altered oxytocin expression in Sert KO mice also indicates a modulation of the oxytocin response by the serotonergic system and provides novel research perspectives with respect to altered response of Sert KO mice to stress and anxiety inducing stimuli.}, subject = {Serotonin}, language = {en} } @phdthesis{Froehlich2011, author = {Fr{\"o}hlich, Matthias}, title = {Die funktionelle Bedeutung der Heteromerisierung von Serotonin-1A und Serotonin-7 Rezeptoren}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-55508}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2011}, abstract = {Die Heterodimerisierung von G- Protein gekoppelten Rezeptoren (GPCR) stellt ein aktuelles Forschungsgebiet dar, das molekulare Erkl{\"a}rungsm{\"o}glichkeiten f{\"u}r die Vielfalt der Signalwege {\"u}ber solche Rezeptoren aufzeigt. Die genauen Funktionen diese Konstrukte in vivo sind bisher erst in Ans{\"a}tzen erforscht, ebenso wenig die molekularbiologischen Mechanismen. F{\"u}r die beiden Serotoninrezeptoren 5-HT1A und 5-HT7 konnte Heterodimerisierung molekular nachgewiesen werden, in ihren physiologischen Mechanismen und Effekten sollte daher eine Charakterisierung vorgenommen werden. Mittels elektrophysiologischer Messverfahren wurden Str{\"o}me an dem heterologen Expressionsmodell der Oozyten des Krallenfrosches Xenopus laevis mittels Voltage-Clamp Technik an Kaliumionenkan{\"a}len (Kir3 und TASK-1) gemessen. Hierbei konnte gezeigt werden, dass die heterodimere Koexpression beider Rezeptoren eine signifikante Reduktion des Rezeptor-aktivierten Kanalstroms im Vergleich zur homomeren Expression zur Folge hatte. Weitere Experimente konnten dann zeigen, dass diese Effekte spezifisch f{\"u}r dieses Rezeptorheterodimer sind, und dass die Effekte von der Dosis bzw. dem Verh{\"a}ltnis der exprimierten cRNA abh{\"a}ngen. In Fluoreszenzmessung konnte zudem gezeigt werden, dass die Reduktion der Stromamplitude in der heterodimeren Expression nicht auf eine Reduktion von Kanalproteinen in der Zellmembran zur{\"u}ckzuf{\"u}hren ist. Zur weiteren Charakterisierung des bisher erst in Ans{\"a}tzen erforschten 5-HT7 Rezeptors wurde dieser abschließend mit einem ß- adrenergen Rezeptor verglichen, der {\"u}ber den gleichen Signalweg bzw. Ionenkanal funktioniert. Auch hier zeigte sich eine signifikante Reduktion des Kanalstroms beim 5-HT7 Rezeptor. Die physiologische Relevanz dieser Ergebnisse liegt darin begr{\"u}ndet, dass ein weiterf{\"u}hrendes Verst{\"a}ndnis von 5-HT Rezeptor vermittelten Signalwegen, insbesondere von der Bedeutung und den Mechanismen ihrer Heterodimersierung, neue pathophysiologische Zusammenh{\"a}nge verdeutlicht. Speziell im Hinblick auf Erkrankungen, die mit den 5-HT Rezeptoren assoziiert sind, wie etwa Depressionen und Angstst{\"o}rungen, soll sich hieraus die M{\"o}glichkeit spezifischerer Therapien ergeben.}, subject = {Heteromerisierung}, language = {de} } @phdthesis{Wittlich2011, author = {Wittlich, Meike}, title = {Interaktionen von allelischen Variationen von 5-HTTLPR mit Umweltfaktoren bei Patienten mit adulter Aufmerksamkeits-Defizit-/ Hyperaktivit{\"a}ts-St{\"o}rung}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-70087}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2011}, abstract = {Dysfunktionen des serotonergen Neurotransmittersystems, innerhalb dessen die allelischen Variationen des 5-HTTLPR-Polymorphismus wiederum einen zentrale Rolle einnehmen, werden f{\"u}r die Genese verschiedener psychischer Erkrankungen diskutiert. Untersucht wurde die Interaktion zwischen der allelischen Variationen des 5-HTTLPR-Polymorphismus und Lebensereignissen, die mit Hilfe des Life History Calendar von Caspi bei 123 aADHS-Patienten erfasst wurden. Die Teilnehmer wurden {\"u}ber Lebenserfahrungen bis zu ihrem 21. Lebensjahr genau befragt, die so in additiver Wertung in den Life-Event-Effekt einflossen. Zudem wurden mit Hilfe der Pers{\"o}nlichkeitstests TPQ und NEO-PI-R Punktescores erhoben. Eine Marker*Life Event-Interaktion wurde nachgewiesen. Bei aAHDS-Patienten, die die homozygot lange Variante des 5-HTTLPR-Polymorphismus tragen, ist eine h{\"o}here Zahl an erlebten Life Events mit einem gr{\"o}ßerem Risiko assoziiert, eine Cluster-B-Pers{\"o}nlichkeitsst{\"o}rung zu entwickeln. Eine geringere Anzahl an Life Events ist assoziiert mit einem geringerem Risiko f{\"u}r Pers{\"o}nlichkeitsst{\"o}rungen.}, subject = {Aufmerksamkeits-Defizit-Syndrom}, language = {de} } @article{AsoHerbOguetaetal.2012, author = {Aso, Yoshinori and Herb, Andrea and Ogueta, Maite and Siwanowicz, Igor and Templier, Thomas and Friedrich, Anja B. and Ito, Kei and Scholz, Henrike and Tanimoto, Hiromu}, title = {Three Dopamine Pathways Induce Aversive Odor Memories with Different Stability}, series = {PLoS Genetics}, volume = {8}, journal = {PLoS Genetics}, number = {7}, doi = {10.1371/journal.pgen.1002768}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-130631}, pages = {e1002768}, year = {2012}, abstract = {Animals acquire predictive values of sensory stimuli through reinforcement. In the brain of Drosophila melanogaster, activation of two types of dopamine neurons in the PAM and PPL1 clusters has been shown to induce aversive odor memory. Here, we identified the third cell type and characterized aversive memories induced by these dopamine neurons. These three dopamine pathways all project to the mushroom body but terminate in the spatially segregated subdomains. To understand the functional difference of these dopamine pathways in electric shock reinforcement, we blocked each one of them during memory acquisition. We found that all three pathways partially contribute to electric shock memory. Notably, the memories mediated by these neurons differed in temporal stability. Furthermore, combinatorial activation of two of these pathways revealed significant interaction of individual memory components rather than their simple summation. These results cast light on a cellular mechanism by which a noxious event induces different dopamine signals to a single brain structure to synthesize an aversive memory.}, language = {en} } @article{KarabegGrauthoffKollertetal.2013, author = {Karabeg, Margherita M. and Grauthoff, Sandra and Kollert, Sina Y. and Weidner, Magdalena and Heiming, Rebecca S. and Jansen, Friederike and Popp, Sandy and Kaiser, Sylvia and Lesch, Klaus-Peter and Sachser, Norbert and Schmitt, Angelika G. and Lewejohann, Lars}, title = {5-HTT Deficiency Affects Neuroplasticity and Increases Stress Sensitivity Resulting in Altered Spatial Learning Performance in the Morris Water Maze but Not in the Barnes Maze}, series = {PLoS ONE}, volume = {8}, journal = {PLoS ONE}, number = {10}, doi = {10.1371/journal.pone.0078238}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-129978}, pages = {e78238}, year = {2013}, abstract = {The purpose of this study was to evaluate whether spatial hippocampus-dependent learning is affected by the serotonergic system and stress. Therefore, 5-HTT knockout (-/-), heterozygous (+/-) and wildtype (+/+) mice were subjected to the Barnes maze (BM) and the Morris water maze (WM), the latter being discussed as more aversive. Additionally, immediate early gene (IEG) expression, hippocampal adult neurogenesis (aN), and blood plasma corticosterone were analyzed. While the performance of 5-HTT-/- mice in the BM was undistinguishable from both other genotypes, they performed worse in the WM. However, in the course of the repeated WM trials 5-HTT-/- mice advanced to wildtype level. The experience of a single trial of either the WM or the BM resulted in increased plasma corticosterone levels in all genotypes. After several trials 5-HTT-/- mice exhibited higher corticosterone concentrations compared with both other genotypes in both tests. Corticosterone levels were highest in 5-HTT-/- mice tested in the WM indicating greater aversiveness of the WM and a greater stress sensitivity of 5-HTT deficient mice. Quantitative immunohistochemistry in the hippocampus revealed increased cell counts positive for the IEG products cFos and Arc as well as for proliferation marker Ki67 and immature neuron marker NeuroD in 5-HTT-/- mice compared to 5-HTT+/+ mice, irrespective of the test. Most differences were found in the suprapyramidal blade of the dentate gyrus of the septal hippocampus. Ki67-immunohistochemistry revealed a genotype x environment interaction with 5-HTT genotype differences in na{\"i}ve controls and WM experience exclusively yielding more Ki67-positive cells in 5-HTT+/+ mice. Moreover, in 5-HTT-/- mice we demonstrate that learning performance correlates with the extent of aN. Overall, higher baseline IEG expression and increased an in the hippocampus of 5-HTT-/- mice together with increased stress sensitivity may constitute the neurobiological correlate of raised alertness, possibly impeding optimal learning performance in the more stressful WM.}, language = {en} } @phdthesis{Gmeiner2014, author = {Gmeiner, Florian}, title = {Der Einfluss der Neurotransmitter Dopamin, Serotonin und GABA sowie ihrer Transporter auf das Schlafverhalten von Drosophila melanogaster}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-99152}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2014}, abstract = {In der vorliegenden Arbeit wurde der Einfluss von Dopamin, Serotonin und GABA auf das Schlafverhalten von Drosophila melanogaster genauer untersucht. Mit Hilfe von Mutanten in Wiederaufnahmetransportern f{\"u}r Dopamin und Serotonin konnte gezeigt werden, dass Dopamin und Serotonin entgegengesetzte Wirkungen auf die Schlafmenge der Fliegen haben. Dopamin hat eine schlafhemmende, Serotonin eine schlaff{\"o}rdernde Wirkung. Die Nutzung eines neuronal dopamindefizienten Fliegenstammes erweitert diese Erkenntnisse. Die Nutzung von RNAi zur Hinunterregulierung der Rezeptoren f{\"u}r Dopamin brachte keine weiteren Erkenntnisse, da sie zu keinem messbaren Effekt f{\"u}hren. Jedoch ergab eine parallel dazu durchgef{\"u}hrte Hinunterregulierung des GABABR2 Rezeptors, dass dieser maßgeblich f{\"u}r die Aufrechterhaltung des Schlafes in der zweiten H{\"a}lfte der Nacht verantwortlich ist. Es konnte gezeigt werden, dass f{\"u}r diese Aufgabe vor allem ihre Expression in den l-LNv Neuronen relevant ist. Dabei ist f{\"u}r die GABABR2 Rezeptoren kein Effekt, f{\"u}r Dopamin und Serotonin nur in geringen Ausmaß ein Effekt auf die Innere Uhr in Form von gering ver{\"a}nderter Periode zu beobachten. Durch eine Kombination der Transportermutanten f{\"u}r Dopamin und Serotonin mit dem intakten, als auch mutierten WHITE Transporter zeigte sich eine interessante Interaktion dieser drei Transporter bei der Regulation der Gesamtschlafmenge, wobei die white Mutation zu einer Reduzierung der Gesamtschlafmenge f{\"u}hrt. UPLC Messungen der St{\"a}mme ergaben, dass der Effekt von white vermutlich auf dessen Einfluss auf den beta-Alanyldopamingehalt der Fliegen basiert. beta-Alanyldopamin wird bei dem Transport von Dopamin {\"u}ber die Gliazellen durch das Enzym EBONY gebildet, dessen Mutation in der Kombination mit intaktem WHITE und mutiertem Dopamintransporter zu einer drastischen Reduktion des Schlafes w{\"a}hrend der Nacht f{\"u}hrt. Im Rahmen der Untersuchung konnte zudem gezeigt werden, dass entgegen des bisherigen Wissens aus Zellkulturstudien in Drosophila melanogaster kein beta-Alanylserotonin gebildet wird. M{\"o}glicherweise wird nur Dopamin, nicht jedoch Serotonin {\"u}ber die Gliazellen recycelt. Dies ist ein interessanter Unterschied, der sowohl eine zeitliche, als auch lokale Feinregulation der Gegenspieler Dopamin und Serotonin erm{\"o}glicht. Die Untersuchung der Dimerpartner BROWN und SCARLET zeigte, dass lediglich BROWN zu einer Reduktion des Schlafes f{\"u}hrt. Ein Effekt, der auch in einer Fliegenlinie mit spontaner white Mutation beobachtet werden konnte. Die genaue Funktion dieses Heterodimertransporters und seine neuronale Lokalisation wurden im Rahmen dieser Arbeit noch nicht gekl{\"a}rt. Dennoch liegt eine Funktion als Dopamin- oder beta-Alanyldopamintransporter in Gliazellen auf Grund der ermittelten Ergebnisse nahe. Zus{\"a}tzlich konnte zum ersten Mal in Drosophila melanogaster eine Funktion der Amintransporter bei der Anpassung der Inneren Uhr an extreme kurze bzw. lange Photoperioden gezeigt werden. Eine anatomische Lokalisierung des WHITE Transporters im Gehirn von Drosophila melanogaster, die weitere Charakterisierung der Rolle des WHITE/BROWN Dimers und die Zuordnung bestimmter dopaminerger und serotonerger Neurone bei der Modulation der Aktivit{\"a}tsmaxima stellen spannende Fragen f{\"u}r zuk{\"u}nftige Arbeiten dar.}, subject = {Taufliege}, language = {de} } @article{KohlGruendlerHuysetal.2015, author = {Kohl, S. and Gruendler, T. O. J. and Huys, D. and Sildatke, E. and Dembek, T. A. and Hellmich, M. and Vorderwulbecke, M. and Timmermann, L. and Ahmari, S. E. and Klosterkoetter, J. and Jessen, F. and Sturm, V. and Visser-Vandewalle, V. and Kuhn, J.}, title = {Effects of deep brain stimulation on prepulse inhibition in obsessive-compulsive disorder}, series = {Translational Psychiatry}, volume = {5}, journal = {Translational Psychiatry}, number = {e675}, doi = {10.1038/tp.2015.171}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-138300}, year = {2015}, abstract = {Owing to a high response rate, deep brain stimulation (DBS) of the ventral striatal area has been approved for treatment-refractory obsessive-compulsive disorder (tr-OCD). Many basic issues regarding DBS for tr-OCD are still not understood, in particular, the mechanisms of action and the origin of side effects. We measured prepulse inhibition (PPI) in treatment-refractory OCD patients undergoing DBS of the nucleus accumbens (NAcc) and matched controls. As PPI has been used in animal DBS studies, it is highly suitable for translational research. Eight patients receiving DBS, eight patients with pharmacological treatment and eight age-matched healthy controls participated in our study. PPI was measured twice in the DBS group: one session with the stimulator switched on and one session with the stimulator switched off. OCD patients in the pharmacologic group took part in a single session. Controls were tested twice, to ensure stability of data. Statistical analysis revealed significant differences between controls and (1) patients with pharmacological treatment and (2) OCD DBS patients when the stimulation was switched off. Switching the stimulator on led to an increase in PPI at a stimulus-onset asynchrony of 200 ms. There was no significant difference in PPI between OCD patients being stimulated and the control group. This study shows that NAcc-DBS leads to an increase in PPI in tr-OCD patients towards a level seen in healthy controls. Assuming that PPI impairments partially reflect the neurobiological substrates of OCD, our results show that DBS of the NAcc may improve sensorimotor gating via correction of dysfunctional neural substrates. Bearing in mind that PPI is based on a complex and multilayered network, our data confirm that DBS most likely takes effect via network modulation.}, language = {en} } @article{WolfBraunHainingetal.2016, author = {Wolf, Karen and Braun, Attila and Haining, Elizabeth J. and Tseng, Yu-Lun and Kraft, Peter and Schuhmann, Michael K. and Gotru, Sanjeev K. and Chen, Wenchun and Hermanns, Heike M. and Stoll, Guido and Lesch, Klaus-Peter and Nieswandt, Bernhard}, title = {Partially Defective Store Operated Calcium Entry and Hem(ITAM) Signaling in Platelets of Serotonin Transporter Deficient Mice}, series = {PLoS One}, volume = {11}, journal = {PLoS One}, number = {1}, doi = {10.1371/journal.pone.0147664}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-146399}, pages = {e0147664}, year = {2016}, abstract = {Background Serotonin (5-hydroxytryptamin, 5-HT) is an indolamine platelet agonist, biochemically derived from tryptophan. 5-HT is secreted from the enterochromaffin cells into the gastrointestinal tract and blood. Blood 5-HT has been proposed to regulate hemostasis by acting as a vasoconstrictor and by triggering platelet signaling through 5-HT receptor 2A (5HTR2A). Although platelets do not synthetize 5-HT, they take 5-HT up from the blood and store it in their dense granules which are secreted upon platelet activation. Objective To identify the molecular composite of the 5-HT uptake system in platelets and elucidate the role of platelet released 5-HT in thrombosis and ischemic stroke. Methods: 5-HT transporter knockout mice (5Htt\(^{-/-}\)) were analyzed in different in vitro and in vivo assays and in a model of ischemic stroke. Results In 5Htt\(^{-/-}\) platelets, 5-HT uptake from the blood was completely abolished and agonist-induced Ca2+ influx through store operated Ca\(^{2+}\) entry (SOCE), integrin activation, degranulation and aggregation responses to glycoprotein VI (GPVI) and C-type lectin-like receptor 2 (CLEC-2) were reduced. These observed in vitro defects in 5Htt\(^{-/-}\) platelets could be normalized by the addition of exogenous 5-HT. Moreover, reduced 5-HT levels in the plasma, an increased bleeding time and the formation of unstable thrombi were observed ex vivo under flow and in vivo in the abdominal aorta and carotid artery of 5Htt\(^{-/-}\) mice. Surprisingly, in the transient middle cerebral artery occlusion (tMCAO) model of ischemic stroke 5Htt\(^{-/-}\) mice showed nearly normal infarct volume and the neurological outcome was comparable to control mice. Conclusion Although secreted platelet 5-HT does not appear to play a crucial role in the development of reperfusion injury after stroke, it is essential to amplify the second phase of platelet activation through SOCE and plays an important role in thrombus stabilization.}, language = {en} } @article{SongJiaZhangetal.2016, author = {Song, Ning-Ning and Jia, Yun-Fang and Zhang, Lei and Zhang, Qiong and Huang, Ying and Liu, Xiao-Zhen and Hu, Ling and Lan, Wei and Chen, Ling and Lesch, Klaus-Peter and Chen, Xiaoyan and Xu, Lin and Ding, Yu-Qiang}, title = {Reducing central serotonin in adulthood promotes hippocampal neurogenesis}, series = {Scientific Reports}, volume = {6}, journal = {Scientific Reports}, number = {20338}, doi = {10.1038/srep20338}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-168004}, year = {2016}, abstract = {Chronic administration of selective serotonin reuptake inhibitors (SSRIs), which up-regulates central serotonin (5-HT) system function, enhances adult hippocampal neurogenesis. However, the relationship between central 5-HT system and adult neurogenesis has not fully been understood. Here, we report that lowering 5-HT level in adulthood is also able to enhance adult hippocampal neurogenesis. We used tamoxifen (TM)-induced Cre in Pet1-CreER\(^{T2}\) mice to either deplete central serotonergic (5-HTergic) neurons or inactivate 5-HT synthesis in adulthood and explore the role of central 5-HT in adult hippocampal neurogenesis. A dramatic increase in hippocampal neurogenesis is present in these two central 5-HT-deficient mice and it is largely prevented by administration of agonist for 5-HTR2c receptor. In addition, the survival of new-born neurons in the hippocampus is enhanced. Furthermore, the adult 5-HT-deficient mice showed reduced depression-like behaviors but enhanced contextual fear memory. These findings demonstrate that lowering central 5-HT function in adulthood can also enhance adult hippocampal neurogenesis, thus revealing a new aspect of central 5-HT in regulating adult neurogenesis.}, language = {en} } @article{FereroRiveroWaeldchenetal.2017, author = {Ferero, Andrea and Rivero, Olga and W{\"a}ldchen, Sina and Ku, Hsing-Ping and Kiser, Dominik P. and G{\"a}rtner, Yvonne and Pennington, Laura S. and Waider, Jonas and Gaspar, Patricia and Jansch, Charline and Edenhofer, Frank and Resink, Th{\´e}r{\`e}se J. and Blum, Robert and Sauer, Markus and Lesch, Klaus-Peter}, title = {Cadherin-13 Deficiency Increases Dorsal Raphe 5-HT Neuron Density and Prefrontal Cortex Innervation in the Mouse Brain}, series = {Frontiers in Cellular Neuroscience}, volume = {11}, journal = {Frontiers in Cellular Neuroscience}, number = {307}, doi = {10.3389/fncel.2017.00307}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-170313}, year = {2017}, abstract = {Background: During early prenatal stages of brain development, serotonin (5-HT)-specific neurons migrate through somal translocation to form the raphe nuclei and subsequently begin to project to their target regions. The rostral cluster of cells, comprising the median and dorsal raphe (DR), innervates anterior regions of the brain, including the prefrontal cortex. Differential analysis of the mouse 5-HT system transcriptome identified enrichment of cell adhesion molecules in 5-HT neurons of the DR. One of these molecules, cadherin-13 (Cdh13) has been shown to play a role in cell migration, axon pathfinding, and synaptogenesis. This study aimed to investigate the contribution of Cdh13 to the development of the murine brain 5-HT system. Methods: For detection of Cdh13 and components of the 5-HT system at different embryonic developmental stages of the mouse brain, we employed immunofluorescence protocols and imaging techniques, including epifluorescence, confocal and structured illumination microscopy. The consequence of CDH13 loss-of-function mutations on brain 5-HT system development was explored in a mouse model of Cdh13 deficiency. Results: Our data show that in murine embryonic brain Cdh13 is strongly expressed on 5-HT specific neurons of the DR and in radial glial cells (RGCs), which are critically involved in regulation of neuronal migration. We observed that 5-HT neurons are intertwined with these RGCs, suggesting that these neurons undergo RGC-guided migration. Cdh13 is present at points of intersection between these two cell types. Compared to wildtype controls, Cdh13-deficient mice display increased cell densities in the DR at embryonic stages E13.5, E17.5, and adulthood, and higher serotonergic innervation of the prefrontal cortex at E17.5. Conclusion: Our findings provide evidence for a role of CDH13 in the development of the serotonergic system in early embryonic stages. Specifically, we indicate that Cdh13 deficiency affects the cell density of the developing DR and the posterior innervation of the prefrontal cortex (PFC), and therefore might be involved in the migration, axonal outgrowth and terminal target finding of DR 5-HT neurons. Dysregulation of CDH13 expression may thus contribute to alterations in this system of neurotransmission, impacting cognitive function, which is frequently impaired in neurodevelopmental disorders including attention-deficit/hyperactivity and autism spectrum disorders.}, language = {en} } @article{WaiderPoppLangeetal.2017, author = {Waider, J and Popp, S and Lange, MD and Kern, R and Kolter, JF and Kobler, J and Donner, NC and Lowe, KR and Malzbender, JH and Brazell, CJ and Arnold, MR and Aboagye, B and Schmitt-B{\"o}hrer, A and Lowry, CA and Pape, HC and Lesch, KP}, title = {Genetically driven brain serotonin deficiency facilitates panic-like escape behavior in mice}, series = {Translational Psychiatry}, volume = {7}, journal = {Translational Psychiatry}, number = {e1246}, doi = {10.1038/tp.2017.209}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-170239}, year = {2017}, abstract = {Multiple lines of evidence implicate brain serotonin (5-hydroxytryptamine; 5-HT) system dysfunction in the pathophysiology of stressor-related and anxiety disorders. Here we investigate the influence of constitutively deficient 5-HT synthesis on stressor-related anxiety-like behaviors using Tryptophan hydroxylase 2 (Tph2) mutant mice. Functional assessment of c-Fos after associated foot shock, electrophysiological recordings of GABAergic synaptic transmission, differential expression of the Slc6a4 gene in serotonergic neurons were combined with locomotor and anxiety-like measurements in different contextual settings. Our findings indicate that constitutive Tph2 inactivation and consequential lack of 5-HT synthesis in Tph2 null mutant mice (Tph2\(^{-/-}\)) results in increased freezing to associated foot shock and a differential c-Fos activity pattern in the basolateral complex of the amygdala. This is accompanied by altered GABAergic transmission as observed by recordings of inhibitory postsynaptic currents on principal neurons in the basolateral nucleus, which may explain increased fear associated with hyperlocomotion and escape-like responses in aversive inescapable contexts. In contrast, lifelong 5-HT deficiency as observed in Tph2 heterozygous mice (Tph\(^{+/-}\)) is able to be compensated through reduced GABAergic transmission in the basolateral nucleus of the amygdala based on Slc6a4 mRNA upregulation in subdivisions of dorsal raphe neurons. This results in increased activity of the basolateral nucleus of the amygdala due to associated foot shock. In conclusion, our results reflect characteristic syndromal dimensions of panic disorder and agoraphobia. Thus, constitutive lack of 5-HT synthesis influence the risk for anxiety- and stressor-related disorders including panic disorder and comorbid agoraphobia through the absence of GABAergic-dependent compensatory mechanisms in the basolateral nucleus of the amygdala.}, language = {en} } @article{WeidnerLardenoijeEijssenetal.2019, author = {Weidner, Magdalena T. and Lardenoije, Roy and Eijssen, Lars and Mogavero, Floriana and De Groodt, Lilian P. M. T. and Popp, Sandy and Palme, Rupert and F{\"o}rstner, Konrad U. and Strekalova, Tatyana and Steinbusch, Harry W. M. and Schmitt-B{\"o}hrer, Angelika G. and Glennon, Jeffrey C. and Waider, Jonas and van den Hove, Daniel L. A. and Lesch, Klaus-Peter}, title = {Identification of cholecystokinin by genome-wide profiling as potential mediator of serotonin-dependent behavioral effects of maternal separation in the amygdala}, series = {Frontiers in Neuroscience}, volume = {13}, journal = {Frontiers in Neuroscience}, doi = {10.3389/fnins.2019.00460}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-201340}, pages = {460}, year = {2019}, abstract = {Converging evidence suggests a role of serotonin (5-hydroxytryptamine, 5-HT) and tryptophan hydroxylase 2 (TPH2), the rate-limiting enzyme of 5-HT synthesis in the brain, in modulating long-term, neurobiological effects of early-life adversity. Here, we aimed at further elucidating the molecular mechanisms underlying this interaction, and its consequences for socio-emotional behaviors, with a focus on anxiety and social interaction. In this study, adult, male Tph2 null mutant (Tph2\(^{-/-}\)) and heterozygous (Tph2\(^{+/-}\)) mice, and their wildtype littermates (Tph2\(^{+/+}\)) were exposed to neonatal, maternal separation (MS) and screened for behavioral changes, followed by genome-wide RNA expression and DNA methylation profiling. In Tph2\(^{-/-}\) mice, brain 5-HT deficiency profoundly affected socio-emotional behaviors, i.e., decreased avoidance of the aversive open arms in the elevated plus-maze (EPM) as well as decreased prosocial and increased rule breaking behavior in the resident-intruder test when compared to their wildtype littermates. Tph2\(^{+/-}\) mice showed an ambiguous profile with context-dependent, behavioral responses. In the EPM they showed similar avoidance of the open arm but decreased prosocial and increased rule breaking behavior in the resident-intruder test when compared to their wildtype littermates. Notably, MS effects on behavior were subtle and depended on the Tph2 genotype, in particular increasing the observed avoidance of EPM open arms in wildtype and Tph2\(^{+/-}\) mice when compared to their Tph2\(^{-/-}\) littermates. On the genomic level, the interaction of Tph2 genotype with MS differentially affected the expression of numerous genes, of which a subset showed an overlap with DNA methylation profiles at corresponding loci. Remarkably, changes in methylation nearby and expression of the gene encoding cholecystokinin, which were inversely correlated to each other, were associated with variations in anxiety-related phenotypes. In conclusion, next to various behavioral alterations, we identified gene expression and DNA methylation profiles to be associated with TPH2 inactivation and its interaction with MS, suggesting a gene-by-environment interaction-dependent, modulatory function of brain 5-HT availability.}, language = {en} } @phdthesis{ForeroEcheverry2020, author = {Forero Echeverry, Andrea Marcela}, title = {Impact of Cadherin-13 deficiency on the brain serotonin system using mouse models and human iPSC-derived neurons}, doi = {10.25972/OPUS-21659}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-216592}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2020}, abstract = {Serotonin (5-hydroxytryptamine, 5-HT) is a neurotransmitter involved in early developmental processes such as cell proliferation, migration, and differentiation. Recent research in humans showed that the brain 5-HT system and CDH13 are interlinked in the genetics of neurodevelopmental disorders including attention- deficit/hyperactivity disorder and autism spectrum disorder (Lesch et al., 2008; Neale et al., 2008; Neale, Medland, Ripke, Anney, et al., 2010; Neale, Medland, Ripke, Asherson, et al., 2010; Sanders et al., 2011; Sanders et al., 2015; Zhou et al., 2008). This study introduces Cadherin-13 (CDH13), a cell adhesion protein, as a contributor to the development and function of the 5-HT system. Our experiments show that the absence of CDH13 increases the density of 5-HT neurons in the developing dorsal raphe (DR) and increases the 5-HT innervation of the prefrontal cortex in mouse embryonic stages. CDH13 is also observed in radial glial cells, an important progenitor cell type linked to neuronal migration. A three-dimensional reconstruction carried out with super-resolution microscopy, identifies 5-HT neurons intertwined with radial glial cells, and CDH13 clusters at contact points between these cells. This indicates a potential contribution of CDH13 to the migration of DR 5-HT neurons. As CDH13 is strongly expressed in 5-HT neurons, we asked whether the selective deletion of CDH13 from these cells is sufficient to generate the alterations observed in the Cdh13 constitutive knockout mouse line. In 5-HT conditional Cdh13 knockout mice (Cdh13 cKO) an increase in DR 5-HT neurons in the embryonic and adult brains is observed, as well as 5-HT hyperinnervation of cortical regions. Therefore, illustrating that the lack of CDH13 from 5-HT neurons alone impacts DR formation and serotonergic innervation. Behavioral testing conducted on Cdh13 cKO mice showed delayed learning in visuospatial learning and memory processing, as well as, changes in sociability parameters. To find out how CDH13 localizes in human 5-HT neurons, CDH13 was visualized in neurons that derived from human induced pluripotent stem cells (iPSC). Super-resolution microscopy confirmed CDH13 expression in a subgroup of induced human neurons positive for typical hallmarks of 5-HT neurons, such as expression of Tph2, the neuron-specific tryptophan hydroxylase, and synaptic structures. In summary, the work included in this thesis presents a detailed analysis of CDH13 expression and localization in the 5-HT system and shows that deletion of CDH13 from 5-HT neurons affects specific higher-order functions of the brain.}, language = {en} } @article{AltieriDiDatoModicaetal.2020, author = {Altieri, Barbara and Di Dato, Carla and Modica, Roberta and Bottiglieri, Filomena and Di Sarno, Antonella and Pittaway, James F.H. and Martini, Chiara and Faggiano, Antongiulio and Colao, Annamaria}, title = {Bone metabolism and vitamin D implication in gastroenteropancreatic neuroendocrine tumors}, series = {Nutrients}, volume = {12}, journal = {Nutrients}, number = {4}, issn = {2072-6643}, doi = {10.3390/nu12041021}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-203823}, year = {2020}, abstract = {Patients affected by gastroenteropancreatic-neuroendocrine tumors (GEP-NETs) have an increased risk of developing osteopenia and osteoporosis, as several factors impact on bone metabolism in these patients. In fact, besides the direct effect of bone metastasis, bone health can be affected by hormone hypersecretion (including serotonin, cortisol, and parathyroid hormone-related protein), specific microRNAs, nutritional status (which in turn could be affected by medical and surgical treatments), and vitamin D deficiency. In patients with multiple endocrine neoplasia type 1 (MEN1), a hereditary syndrome associated with NET occurrence, bone damage may carry other consequences. Osteoporosis may negatively impact on the quality of life of these patients and can increment the cost of medical care since these patients usually live with their disease for a long time. However, recommendations suggesting screening to assess bone health in GEP-NET patients are missing. The aim of this review is to critically analyze evidence on the mechanisms that could have a potential impact on bone health in patients affected by GEP-NET, focusing on vitamin D and its role in GEP-NET, as well as on factors associated with MEN1 that could have an impact on bone homeostasis.}, language = {en} } @article{GriebschKernHansenetal.2022, author = {Griebsch, Nora-Isabell and Kern, Johanna and Hansen, Jonas and Rullmann, Michael and Luthardt, Julia and Helfmeyer, Stephanie and Dekorsy, Franziska J. and Soeder, Marvin and Hankir, Mohammed K. and Zientek, Franziska and Becker, Georg-Alexander and Patt, Marianne and Meyer, Philipp M. and Dietrich, Arne and Bl{\"u}her, Matthias and Ding, Yu-Shin and Hilbert, Anja and Sabri, Osama and Hesse, Swen}, title = {Central serotonin/noradrenaline transporter availability and treatment success in patients with obesity}, series = {Brain Sciences}, volume = {12}, journal = {Brain Sciences}, number = {11}, issn = {2076-3425}, doi = {10.3390/brainsci12111437}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-290294}, year = {2022}, abstract = {Serotonin (5-hydroxytryptamine, 5-HT) as well as noradrenaline (NA) are key modulators of various fundamental brain functions including the control of appetite. While manipulations that alter brain serotoninergic signaling clearly affect body weight, studies implicating 5-HT transporters and NA transporters (5-HTT and NAT, respectively) as a main drug treatment target for human obesity have not been conclusive. The aim of this positron emission tomography (PET) study was to investigate how these central transporters are associated with changes of body weight after 6 months of dietary intervention or Roux-en-Y gastric bypass (RYGB) surgery in order to assess whether 5-HTT as well as NAT availability can predict weight loss and consequently treatment success. The study population consisted of two study cohorts using either the 5-HTT-selective radiotracer [\(^{11}\)C]DASB to measure 5-HTT availability or the NAT-selective radiotracer [\(^{11}\)C]MRB to assess NAT availability. Each group included non-obesity healthy participants, patients with severe obesity (body mass index, BMI, >35 kg/m\(^2\)) following a conservative dietary program (diet) and patients undergoing RYGB surgery within a 6-month follow-up. Overall, changes in BMI were not associated with changes of both 5-HTT and NAT availability, while 5-HTT availability in the dorsal raphe nucleus (DRN) prior to intervention was associated with substantial BMI reduction after RYGB surgery and inversely related with modest BMI reduction after diet. Taken together, the data of our study indicate that 5-HTT and NAT are involved in the pathomechanism of obesity and have the potential to serve as predictors of treatment outcomes.}, language = {en} }