@article{AraragiMlinarBaccinietal.2013,
  author    = {Araragi, Naozumi and Mlinar, Boris and Baccini, Gilda and Gutknecht, Lise and Lesch, Klaus-Peter and Corradetti, Renato},
  title     = {Conservation of 5-HT1A receptor-mediated autoinhibition of serotonin (5-HT) neurons in mice with altered 5-HT homeostasis},
  series = {Frontiers in Neuropharmacology},
  journal   = {Frontiers in Neuropharmacology},
  doi       = {10.3389/fphar.2013.00097},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-97098},
  year      = {2013},
  abstract  = {Firing activity of serotonin (5-HT) neurons in the dorsal raphe nucleus (DRN) is controlled by inhibitory somatodendritic 5-HT1A autoreceptors. This autoinhibitory mechanism is implicated in the etiology of disorders of emotion regulation, such as anxiety disorders and depression, as well as in the mechanism of antidepressant action. Here, we investigated how persistent alterations in brain 5-HT availability affect autoinhibition in two genetically modified mouse models lacking critical mediators of serotonergic transmission: 5-HT transporter knockout (Sert-/-) and tryptophan hydroxylase-2 knockout (Tph2-/-) mice. The degree of autoinhibition was assessed by loose-seal cell-attached recording in DRN slices. First, application of the 5-HT1A-selective agonist R(+)-8-hydroxy-2-(di-n-propylamino)tetralin showed mild sensitization and marked desensitization of 5-HT1A receptors in Tph2-/- mice and Sert-/- mice, respectively. While 5-HT neurons from Tph2-/- mice did not display autoinhibition in response to L-tryptophan, autoinhibition of these neurons was unaltered in Sert-/- mice despite marked desensitization of their 5-HT1A autoreceptors. When the Tph2-dependent 5-HT synthesis step was bypassed by application of 5-hydroxy-L-tryptophan (5-HTP), neurons from both Tph2-/- and Sert-/- mice decreased their firing rates at significantly lower concentrations of 5-HTP compared to wildtype controls. Our findings demonstrate that, as opposed to the prevalent view, sensitivity of somatodendritic 5-HT1A receptors does not predict the magnitude of 5-HT neuron autoinhibition. Changes in 5-HT1A receptor sensitivity may rather be seen as an adaptive mechanism to keep autoinhibition functioning in response to extremely altered levels of extracellular 5-HT resulting from targeted inactivation of mediators of serotonergic signaling.},
  language  = {en}
}
@article{StrekalovaVeniaminovaSvirinetal.2021,
  author    = {Strekalova, Tatyana and Veniaminova, Ekaterina and Svirin, Evgeniy and Kopeikina, Ekaterina and Veremeyko, Tatyana and Yung, Amanda W. Y. and Proshin, Andrey and Tan, Shawn Zheng Kai and Khairuddin, Sharafuddin and Lim, Lee Wei and Lesch, Klaus-Peter and Walitza, Susanne and Anthony, Daniel C. and Ponomarev, Eugene D.},
  title     = {Sex-specific ADHD-like behaviour, altered metabolic functions, and altered EEG activity in sialyltransferase ST3GAL5-deficient mice},
  series = {Biomolecules},
  volume    = {11},
  journal   = {Biomolecules},
  number    = {12},
  issn      = {2218-273X},
  doi       = {10.3390/biom11121759},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-250071},
  year      = {2021},
  abstract  = {A deficiency in GM3-derived gangliosides, resulting from a lack of lactosylceramide-alpha-2,3-sialyltransferase (ST3GAL5), leads to severe neuropathology, including epilepsy and metabolic abnormalities. Disruption of ganglioside production by this enzyme may also have a role in the development of neuropsychiatric disorders. ST3Gal5 knock-out (St3gal5\(^{-/-}\)) mice lack a-, b-, and c-series gangliosides, but exhibit no overt neuropathology, possibly owing to the production of compensatory 0-series glycosphingolipids. Here, we sought to investigate the possibility that St3gal5\(^{-/-}\) mice might exhibit attention-deficit/hyperactivity disorder (ADHD)-like behaviours. In addition, we evaluated potential metabolic and electroencephalogram (EEG) abnormalities. St3gal5\(^{-/-}\) mice were subjected to behavioural testing, glucose tolerance tests, and the levels of expression of brain and peripheral A and B isoforms of the insulin receptor (IR) were measured. We found that St3gal5\(^{-/-}\) mice exhibit locomotor hyperactivity, impulsivity, neophobia, and anxiety-like behavior. The genotype also altered blood glucose levels and glucose tolerance. A sex bias was consistently found in relation to body mass and peripheral IR expression. Analysis of the EEG revealed an increase in amplitude in St3gal5\(^{-/-}\) mice. Together, St3gal5\(^{-/-}\) mice exhibit ADHD-like behaviours, altered metabolic and EEG measures providing a useful platform for better understanding of the contribution of brain gangliosides to ADHD and associated comorbidities.},
  language  = {en}
}
@article{SvirinVeniaminovaCostaNunesetal.2022,
  author    = {Svirin, Evgeniy and Veniaminova, Ekaterina and Costa-Nunes, Jo{\~a}o Pedro and Gorlova, Anna and Umriukhin, Aleksei and Kalueff, Allan V. and Proshin, Andrey and Anthony, Daniel C. and Nedorubov, Andrey and Tse, Anna Chung Kwan and Walitza, Susanne and Lim, Lee Wei and Lesch, Klaus-Peter and Strekalova, Tatyana},
  title     = {Predation stress causes excessive aggression in female mice with partial genetic inactivation of tryptophan hydroxylase-2: evidence for altered myelination-related processes},
  series = {Cells},
  volume    = {11},
  journal   = {Cells},
  number    = {6},
  issn      = {2073-4409},
  doi       = {10.3390/cells11061036},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-267250},
  year      = {2022},
  abstract  = {The interaction between brain serotonin (5-HT) deficiency and environmental adversity may predispose females to excessive aggression. Specifically, complete inactivation of the gene encoding tryptophan hydroxylase-2 (Tph2) results in the absence of neuronal 5-HT synthesis and excessive aggressiveness in both male and female null mutant (Tph2\(^{-/-}\)) mice. In heterozygous male mice (Tph2\(^{+/-}\)), there is a moderate reduction in brain 5-HT levels, and when they are exposed to stress, they exhibit increased aggression. Here, we exposed female Tph2\(^{+/-}\) mice to a five-day rat predation stress paradigm and assessed their emotionality and social interaction/aggression-like behaviors. Tph2\(^{+/-}\) females exhibited excessive aggression and increased dominant behavior. Stressed mutants displayed altered gene expression of the 5-HT receptors Htr1a and Htr2a, glycogen synthase kinase-3 β (GSK-3β), and c-fos as well as myelination-related transcripts in the prefrontal cortex: myelin basic protein (Mbp), proteolipid protein 1 (Plp1), myelin-associated glycoprotein (Mag), and myelin oligodendrocyte glycoprotein (Mog). The expression of the plasticity markers synaptophysin (Syp) and cAMP response element binding protein (Creb), but not AMPA receptor subunit A2 (GluA2), were affected by genotype. Moreover, in a separate experiment, na{\"i}ve female Tph2\(^{+/-}\) mice showed signs of enhanced stress resilience in the modified swim test with repeated swimming sessions. Taken together, the combination of a moderate reduction in brain 5-HT with environmental challenges results in behavioral changes in female mice that resemble the aggression-related behavior and resilience seen in stressed male mutants; additionally, the combination is comparable to the phenotype of null mutants lacking neuronal 5-HT. Changes in myelination-associated processes are suspected to underpin the molecular mechanisms leading to aggressive behavior.},
  language  = {en}
}
@article{GrimmWeberKittelSchneideretal.2020,
  author    = {Grimm, Oliver and Weber, Heike and Kittel-Schneider, Sarah and Kranz, Thorsten M. and Jacob, Christian P. and Lesch, Klaus-Peter and Reif, Andreas},
  title     = {Impulsivity and Venturesomeness in an Adult ADHD Sample: Relation to Personality, Comorbidity, and Polygenic Risk},
  series = {Frontiers in Psychiatry},
  volume    = {11},
  journal   = {Frontiers in Psychiatry},
  issn      = {1664-0640},
  doi       = {10.3389/fpsyt.2020.557160},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-219751},
  year      = {2020},
  abstract  = {While impulsivity is a basic feature of attention-deficit/hyperactivity disorder (ADHD), no study explored the effect of different components of the Impulsiveness (Imp) and Venturesomeness (Vent) scale (IV7) on psychiatric comorbidities and an ADHD polygenic risk score (PRS). We used the IV7 self-report scale in an adult ADHD sample of 903 patients, 70\% suffering from additional comorbid disorders, and in a subsample of 435 genotyped patients. Venturesomeness, unlike immediate Impulsivity, is not specific to ADHD. We consequently analyzed the influence of Imp and Vent also in the context of a PRS on psychiatric comorbidities of ADHD. Vent shows a distinctly different distribution of comorbidities, e.g., less anxiety and depression. PRS showed no effect on different ADHD comorbidities, but correlated with childhood hyperactivity. In a complementary analysis using principal component analysis with Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition ADHD criteria, revised NEO Personality Inventory, Imp, Vent, and PRS, we identified three ADHD subtypes. These are an impulsive-neurotic type, an adventurous-hyperactive type with a stronger genetic component, and an anxious-inattentive type. Our study thus suggests the importance of adventurousness and the differential consideration of impulsivity in ADHD. The genetic risk is distributed differently between these subtypes, which underlines the importance of clinically motivated subtyping. Impulsivity subtyping might give insights into the organization of comorbid disorders in ADHD and different genetic background.},
  language  = {en}
}
@article{WaiderPoppMlinaretal.2019,
  author    = {Waider, Jonas and Popp, Sandy and Mlinar, Boris and Montalbano, Alberto and Bonfiglio, Francesco and Aboagye, Benjamin and Thuy, Elisabeth and Kern, Raphael and Thiel, Christopher and Araragi, Naozumi and Svirin, Evgeniy and Schmitt-B{\"o}hrer, Angelika G. and Corradetti, Renato and Lowry, Christopher A. and Lesch, Klaus-Peter},
  title     = {Serotonin deficiency increases context-dependent fear learning through modulation of hippocampal activity},
  series = {Frontiers in Neuroscience},
  volume    = {13},
  journal   = {Frontiers in Neuroscience},
  number    = {245},
  issn      = {1662-453X},
  doi       = {10.3389/fnins.2019.00245},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-196077},
  year      = {2019},
  abstract  = {Brain serotonin (5-hydroxytryptamine, 5-HT) system dysfunction is implicated in exaggerated fear responses triggering various anxiety-, stress-, and trauma-related disorders. However, the underlying mechanisms are not well understood. Here, we investigated the impact of constitutively inactivated 5-HT synthesis on context-dependent fear learning and extinction using tryptophan hydroxylase 2 (Tph2) knockout mice. Fear conditioning and context-dependent fear memory extinction paradigms were combined with c-Fos imaging and electrophysiological recordings in the dorsal hippocampus (dHip). Tph2 mutant mice, completely devoid of 5-HT synthesis in brain, displayed accelerated fear memory formation and increased locomotor responses to foot shock. Furthermore, recall of context-dependent fear memory was increased. The behavioral responses were associated with increased c-Fos expression in the dHip and resistance to foot shock-induced impairment of hippocampal long-term potentiation (LTP). In conclusion, increased context-dependent fear memory resulting from brain 5-HT deficiency involves dysfunction of the hippocampal circuitry controlling contextual representation of fear-related behavioral responses.},
  language  = {en}
}
@article{ClineCostaNunesCespuglioetal.2015,
  author    = {Cline, Brandon H. and Costa-Nunes, Joao P. and Cespuglio, Raymond and Markova, Natalyia and Santos, Ana I. and Bukhman, Yury V. and Kubatiev, Aslan and Steinbusch, Harry W. M. and Lesch, Klaus-Peter and Strekalova, Tatyana},
  title     = {Dicholine succinate, the neuronal insulin sensitizer, normalizes behavior, REM sleep, hippocampal pGSK3 beta and mRNAs of NMDA receptor subunits in mouse models of depression},
  series = {Frontiers in Behavioral Neuroscience},
  volume    = {9},
  journal   = {Frontiers in Behavioral Neuroscience},
  number    = {37},
  doi       = {10.3389/fnbeh.2015.00037},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-143992},
  year      = {2015},
  abstract  = {Central insulin receptor-mediated signaling is attracting the growing attention of researchers because of rapidly accumulating evidence implicating it in the mechanisms of plasticity, stress response, and neuropsychiatric disorders including depression. Dicholine succinate (DS), a mitochondrial complex II substrate, was shown to enhance insulin-receptor mediated signaling in neurons and is regarded as a sensitizer of the neuronal insulin receptor. Compounds enhancing neuronal insulin receptor-mediated transmission exert an antidepressant-like effect in several pre-clinical paradigms of depression; similarly, such properties for DS were found with a stress-induced anhedonia model. Here, we additionally studied the effects of DS on several variables which were ameliorated by other insulin receptor sensitizers in mice. Pre-treatment with DS of chronically stressed C57BL6 mice rescued normal contextual fear conditioning, hippocampal gene expression of NMDA receptor subunit NR2A, the NR2A/NR2B ratio and increased REM sleep rebound after acute predation. In 18-month-old C57BL6 mice, a model of elderly depression, DS restored normal sucrose preference and activated the expression of neural plasticity factors in the hippocampus as shown by Illumina microarray. Finally, young naive DS-treated C57BL6 mice had reduced depressive- and anxiety-like behaviors and, similarly to imipramine-treated mice, preserved hippocampal levels of the phosphorylated (inactive) form of GSK3 beta that was lowered by forced swimming in pharmacologically naive animals. Thus, DS can ameliorate behavioral and molecular outcomes under a variety of stress- and depression-related conditions. This further highlights neuronal insulin signaling as a new factor of pathogenesis and a potential pharmacotherapy of affective pathologies.},
  language  = {en}
}
@article{JuhaszGondaHullametal.2015,
  author    = {Juhasz, Gabriella and Gonda, Xenia and Hullam, Gabor and Eszlari, Nora and Kovacs, David and Lazary, Judit and Pap, Dorottya and Petschner, Peter and Elliott, Rebecca and Deakin, John Francis William and Muir Anderson, Ian and Antal, Peter and Lesch, Klaus-Peter and Bagdy, Gyorgy},
  title     = {Variability in the effect of 5-HTTLPR on depression in a large European population: the role of age, symptom profile, type and intensity of life stressors},
  series = {PLoS ONE},
  volume    = {10},
  journal   = {PLoS ONE},
  number    = {3},
  doi       = {10.1371/journal.pone.0116316},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-143703},
  pages     = {e0116316},
  year      = {2015},
  abstract  = {Background Although 5-HTTLPR has been shown to influence the risk of life stress-induced depression in the majority of studies, others have produced contradictory results, possibly due to weak effects and/or sample heterogeneity. Methods In the present study we investigated how age, type and intensity of life-stressors modulate the effect of 5-HTTLPR on depression and anxiety in a European population cohort of over 2300 subjects. Recent negative life events (RLE), childhood adversity (CHA), lifetime depression, Brief Symptoms Inventory (BSI) depression and anxiety scores were determined in each subject. Besides traditional statistical analysis we calculated Bayesian effect strength and relevance of 5-HTTLPR genotypes in specified models. Results The short (s) low expressing allele showed association with increased risk of depression related phenotypes, but all nominally significant effects would turn to non-significant after correction for multiple testing in the traditional analysis. Bayesian effect strength and relevance analysis, however, confirmed the role of 5-HTTLPR. Regarding current (BSI) and lifetime depression 5-HTTLPR-by-RLE interactions were confirmed. Main effect, with other words direct association, was supported with BSI anxiety. With more frequent RLE the prevalence or symptoms of depression increased in ss carriers. Although CHA failed to show an interaction with 5-HTTLPR, in young subjects CHA sensitized towards the depression promoting effect of even mild RLE. Furthermore, the direct association of anxiety with the s allele was driven by young (\(\leq\)30) individuals. Limitations Our study is cross-sectional and applies self-report questionnaires. Conclusions Albeit 5-HTTLPR has only weak/moderate effects, the s allele is directly associated with anxiety and modulates development of depression in homogeneous subgroups.},
  language  = {en}
}
@article{BoddenRichterSchreiberetal.2015,
  author    = {Bodden, Carina and Richter, S. Helene and Schreiber, Rebecca S. and Kloke, Vanessa and Gerß, Joachim and Palme, Rupert and Lesch, Klaus-Peter and Lewejohann, Lars and Kaiser, Sylvia and Sachser, Norbert},
  title     = {Benefits of adversity?! How life history affects the behavioral profile of mice varying in serotonin transporter genotype},
  series = {Frontiers in Behavioral Neuroscience},
  volume    = {9},
  journal   = {Frontiers in Behavioral Neuroscience},
  number    = {47},
  doi       = {10.3389/fnbeh.2015.00047},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-143723},
  year      = {2015},
  abstract  = {Behavioral profiles are influenced by both positive and negative experiences as well as the genetic disposition. Traditionally, accumulating adversity over lifetime is considered to predict increased anxiety like behavior ("allostatic load"). The alternative "mismatch hypothesis" suggests increased levels of anxiety if the early environment differs from the later-life environment. Thus, there is a need for a whole-life history approach to gain a deeper understanding of how behavioral profiles are shaped. The aim of this study was to elucidate the effects of life history on the behavioral profile of mice varying in serotonin transporter (5-HIT) genotype, an established mouse model of increased anxiety-like behavior. For this purpose, mice grew up under either adverse or beneficial conditions during early phases of life. In adulthood, they were further subdivided so as to face a situation that either matched or mismatched the condition experienced so far, resulting in four different life histories. Subsequently, mice were tested for their anxiety-like and exploratory behavior. The main results were: (1) Life history profoundly modulated the behavioral profile. Surprisingly, mice that experienced early beneficial and later escapable adverse conditions showed less anxiety-like and more exploratory behavior compared to mice of other life histories. (2) Genotype significantly influenced the behavioral profile, with homozygous 5-HTT knockout mice displaying highest levels of anxiety-like and lowest levels of exploratory behavior. Our findings concerning life history indicate that the absence of adversity does not necessarily cause lower levels of anxiety than accumulating adversity. Rather, some adversity may be beneficial, particularly when following positive events. Altogether, we conclude that for an understanding of behavioral profiles, it is not sufficient to look at experiences during single phases of life, but the whole life history has to be considered.},
  language  = {en}
}
@article{StrekalovaPavlovTrofimovetal.2022,
  author    = {Strekalova, Tatyana and Pavlov, Dmitrii and Trofimov, Alexander and Anthony, Daniel C. and Svistunov, Andrei and Proshin, Andrey and Umriukhin, Aleksei and Lyundup, Alexei and Lesch, Klaus-Peter and Cespuglio, Raymond},
  title     = {Hippocampal over-expression of cyclooxygenase-2 (COX-2) is associated with susceptibility to stress-induced anhedonia in mice},
  series = {International Journal of Molecular Sciences},
  volume    = {23},
  journal   = {International Journal of Molecular Sciences},
  number    = {4},
  issn      = {1422-0067},
  doi       = {10.3390/ijms23042061},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-284056},
  year      = {2022},
  abstract  = {The phenomenon of individual variability in susceptibility/resilience to stress and depression, in which the hippocampus plays a pivotal role, is attracting increasing attention. We investigated the potential role of hippocampal cyclooxygenase-2 (COX-2), which regulates plasticity, neuroimmune function, and stress responses that are all linked to this risk dichotomy. We used a four-week-long chronic mild stress (CMS) paradigm, in which mice could be stratified according to their susceptibility/resilience to anhedonia, a key feature of depression, to investigate hippocampal expression of COX-2, a marker of microglial activation Iba-1, and the proliferation marker Ki67. Rat exposure, social defeat, restraints, and tail suspension were used as stressors. We compared the effects of treatment with either the selective COX-2 inhibitor celecoxib (30 mg/kg/day) or citalopram (15 mg/kg/day). For the celecoxib and vehicle-treated mice, the Porsolt test was used. Anhedonic (susceptible) but not non-anhedonic (resilient) animals exhibited elevated COX-2 mRNA levels, increased numbers of COX-2 and Iba-1-positive cells in the dentate gyrus and the CA1 area, and decreased numbers of Ki67-positive cells in the subgranular zone of the hippocampus. Drug treatment decreased the percentage of anhedonic mice, normalized swimming activity, reduced behavioral despair, and improved conditioned fear memory. Hippocampal over-expression of COX-2 is associated with susceptibility to stress-induced anhedonia, and its pharmacological inhibition with celecoxib has antidepressant effects that are similar in size to those of citalopram.},
  language  = {en}
}
@article{BrevikvanDonkelaarWeberetal.2016,
  author    = {Brevik, Erlend J and van Donkelaar, Marjolein M. J. and Weber, Heike and S{\´a}nchez-Mora, Cristina and Jacob, Christian and Rivero, Olga and Kittel-Schneider, Sarah and Garcia-martinez, Iris and Aebi, Marcel and van Hulzen, Kimm and Cormand, Bru and Ramos-Quiroga, Josep A and Lesch, Klaus-Peter and Reif, Andreas and Ribases, Marta and Franke, Barbara and Posserud, Maj-Britt and Johansson, Stefan and Lundervold, Astri J. and Haavik, Jan and Zayats, Tetyana},
  title     = {Genome-wide analyses of aggressiveness in attention-deficit hyperactivity disorder},
  series = {American Journal of Medical Genetics Part B-Neuropsychiatric Genetics},
  volume    = {171B},
  journal   = {American Journal of Medical Genetics Part B-Neuropsychiatric Genetics},
  number    = {5},
  organization    = {IMAGE Consortium},
  doi       = {10.1002/ajmg.b.32434},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-188116},
  pages     = {733-747},
  year      = {2016},
  abstract  = {Aggressiveness is a behavioral trait that has the potential to be harmful to individuals and society. With an estimated heritability of about 40\%, genetics is important in its development. We performed an exploratory genome-wide association (GWA) analysis of childhood aggressiveness in attention deficit hyperactivity disorder (ADHD) to gain insight into the underlying biological processes associated with this trait. Our primary sample consisted of 1,060 adult ADHD patients (aADHD). To further explore the genetic architecture of childhood aggressiveness, we performed enrichment analyses of suggestive genome-wide associations observed in aADHD among GWA signals of dimensions of oppositionality (defiant/vindictive and irritable dimensions) in childhood ADHD (cADHD). No single polymorphism reached genome-wide significance (P<5.00E-08). The strongest signal in aADHD was observed at rs10826548, within a long noncoding RNA gene (beta = -1.66, standard error (SE) = 0.34, P = 1.07E-06), closely followed by rs35974940 in the neurotrimin gene (beta = 3.23, SE = 0.67, P = 1.26E-06). The top GWA SNPs observed in aADHD showed significant enrichment of signals from both the defiant/vindictive dimension (Fisher's P-value = 2.28E-06) and the irritable dimension in cADHD (Fisher's P-value = 0.0061). In sum, our results identify a number of biologically interesting markers possibly underlying childhood aggressiveness and provide targets for further genetic exploration of aggressiveness across psychiatric disorders.},
  language  = {en}
}
@article{SchaeferFriedrichJorgensenetal.2018,
  author    = {Sch{\"a}fer, Nadine and Friedrich, Maximilian and J{\o}rgensen, Morten Egevang and Kollert, Sina and Koepsell, Hermann and Wischmeyer, Erhard and Lesch, Klaus-Peter and Geiger, Dietmar and D{\"o}ring, Frank},
  title     = {Functional analysis of a triplet deletion in the gene encoding the sodium glucose transporter 3, a potential risk factor for ADHD},
  series = {PLoS ONE},
  volume    = {13},
  journal   = {PLoS ONE},
  number    = {10},
  doi       = {10.1371/journal.pone.0205109},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-176495},
  pages     = {e0205109},
  year      = {2018},
  abstract  = {Sodium-glucose transporters (SGLT) belong to the solute carrier 5 family, which is characterized by sodium dependent transport of sugars and other solutes. In contrast, the human SGLT3 (hSGLT3) isoform, encoded by SLC5A4, acts as a glucose sensor that does not transport sugar but induces membrane depolarization by Na\(^{+}\) currents upon ligand binding. Whole-exome sequencing (WES) of several extended pedigrees with high density of attention-deficit/hyperactivity disorder (ADHD) identified a triplet ATG deletion in SLC5A4 leading to a single amino acid loss (ΔM500) in the hSGLT3 protein imperfectly co-segregating with the clinical phenotype of ADHD. Since mutations in homologous domains of hSGLT1 and hSGLT2 were found to affect intestinal and renal function, respectively, we analyzed the functional properties of hSGLT3[wt] and [ΔM500] by voltage clamp and current clamp recordings from cRNA-injected Xenopus laevis oocytes. The cation conductance of hSGLT3[wt] was activated by application of glucose or the specific agonist 1-desoxynojirimycin (DNJ) as revealed by inward currents in the voltage clamp configuration and cell depolarization in the current clamp mode. Almost no currents and changes in membrane potential were observed when glucose or DNJ were applied to hSGLT3[ΔM500]-injected oocytes, demonstrating a loss of function by this amino acid deletion in hSGLT3. To monitor membrane targeting of wt and mutant hSGLT3, fusion constructs with YFP were generated, heterologously expressed in Xenopus laevis oocytes and analyzed for membrane fluorescence by confocal microscopy. In comparison to hSGLT3[wt] the fluorescent signal of mutant [ΔM500] was reduced by 43\% indicating that the mutant phenotype might mainly result from inaccurate membrane targeting. As revealed by homology modeling, residue M500 is located in TM11 suggesting that in addition to the core structure (TM1-TM10) of the transporter, the surrounding TMs are equally crucial for transport/sensor function. In conclusion, our findings indicate that the deletion [ΔM500] in hSGLT3 inhibits membrane targeting and thus largely disrupts glucose-induced sodium conductance, which may, in interaction with other ADHD risk-related gene variants, influence the risk for ADHD in deletion carriers.},
  language  = {en}
}
@article{VeniaminovaCespuglioCheungetal.2017,
  author    = {Veniaminova, Ekaterina and Cespuglio, Raymond and Cheung, Chi Wai and Umriukhin, Alexei and Markova, Nataliia and Shevtsova, Elena and Lesch, Klaus-Peter and Anthony, Daniel C. and Strekalova, Tatyana},
  title     = {Autism-like behaviours and memory deficits result from a Western Diet in mice},
  series = {Neural Plasticity},
  journal   = {Neural Plasticity},
  doi       = {10.1155/2017/9498247},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-158211},
  pages     = {9498247},
  year      = {2017},
  abstract  = {Nonalcoholic fatty liver disease, induced by a Western diet (WD), evokes central and peripheral inflammation that is accompanied by altered emotionality. These changes can be associated with abnormalities in social behaviour, hippocampus-dependent cognitive functions, and metabolism. Female C57BL/6J mice were fed with a regular chow or with a WD containing 0.2\% of cholesterol and 21\% of saturated fat for three weeks. WD-treated mice exhibited increased social avoidance, crawl-over and digging behaviours, decreased body-body contacts, and hyperlocomotion. The WD-fed group also displayed deficits in hippocampal-dependent performance such as contextual memory in a fear conditioning and pellet displacement paradigms. A reduction in glucose tolerance and elevated levels of serum cholesterol and leptin were also associated with the WD. The peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PPARGC1a) mRNA, a marker of mitochondrial activity, was decreased in the prefrontal cortex, hippocampus, hypothalamus, and dorsal raphe, suggesting suppressed brain mitochondrial functions, but not in the liver. This is the first report to show that a WD can profoundly suppress social interactions and induce dominant-like behaviours in na{\"i}ve adult mice. The spectrum of behaviours that were found to be induced are reminiscent of symptoms associated with autism, and, if paralleled in humans, suggest that a WD might exacerbate autism spectrum disorder.},
  language  = {en}
}
@article{ReuterJaeckelsKneitzetal.2019,
  author    = {Reuter, Isabel and J{\"a}ckels, Jana and Kneitz, Susanne and Kuper, Jochen and Lesch, Klaus-Peter and Lillesaar, Christina},
  title     = {Fgf3 is crucial for the generation of monoaminergic cerebrospinal fluid contacting cells in zebrafish},
  series = {Biology Open},
  volume    = {8},
  journal   = {Biology Open},
  doi       = {10.1242/bio.040683},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-200749},
  pages     = {bio040683},
  year      = {2019},
  abstract  = {In most vertebrates, including zebrafish, the hypothalamic serotonergic cerebrospinal fluid-contacting (CSF-c) cells constitute a prominent population. In contrast to the hindbrain serotonergic neurons, little is known about the development and function of these cells. Here, we identify fibroblast growth factor (Fgf)3 as the main Fgf ligand controlling the ontogeny of serotonergic CSF-c cells. We show that fgf3 positively regulates the number of serotonergic CSF-c cells, as well as a subset of dopaminergic and neuroendocrine cells in the posterior hypothalamus via control of proliferation and cell survival. Further, expression of the ETS-domain transcription factor etv5b is downregulated after fgf3 impairment. Previous findings identified etv5b as critical for the proliferation of serotonergic progenitors in the hypothalamus, and therefore we now suggest that Fgf3 acts via etv5b during early development to ultimately control the number of mature serotonergic CSF-c cells. Moreover, our analysis of the developing hypothalamic transcriptome shows that the expression of fgf3 is upregulated upon fgf3 loss-of-function, suggesting activation of a self-compensatory mechanism. Together, these results highlight Fgf3 in a novel context as part of a signalling pathway of critical importance for hypothalamic development.},
  language  = {en}
}
@article{GorlovaSvirinPavlovetal.2023,
  author    = {Gorlova, Anna and Svirin, Evgeniy and Pavlov, Dmitrii and Cespuglio, Raymond and Proshin, Andrey and Schroeter, Careen A. and Lesch, Klaus-Peter and Strekalova, Tatyana},
  title     = {Understanding the role of oxidative stress, neuroinflammation and abnormal myelination in excessive aggression associated with depression: recent input from mechanistic studies},
  series = {International Journal of Molecular Sciences},
  volume    = {24},
  journal   = {International Journal of Molecular Sciences},
  number    = {2},
  issn      = {1422-0067},
  doi       = {10.3390/ijms24020915},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-304917},
  year      = {2023},
  abstract  = {Aggression and deficient cognitive control problems are widespread in psychiatric disorders, including major depressive disorder (MDD). These abnormalities are known to contribute significantly to the accompanying functional impairment and the global burden of disease. Progress in the development of targeted treatments of excessive aggression and accompanying symptoms has been limited, and there exists a major unmet need to develop more efficacious treatments for depressed patients. Due to the complex nature and the clinical heterogeneity of MDD and the lack of precise knowledge regarding its pathophysiology, effective management is challenging. Nonetheless, the aetiology and pathophysiology of MDD has been the subject of extensive research and there is a vast body of the latest literature that points to new mechanisms for this disorder. Here, we overview the key mechanisms, which include neuroinflammation, oxidative stress, insulin receptor signalling and abnormal myelination. We discuss the hypotheses that have been proposed to unify these processes, as many of these pathways are integrated for the neurobiology of MDD. We also describe the current translational approaches in modelling depression, including the recent advances in stress models of MDD, and emerging novel therapies, including novel approaches to management of excessive aggression, such as anti-diabetic drugs, antioxidant treatment and herbal compositions.},
  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}
}
@article{VitaleZoellerJanschetal.2021,
  author    = {Vitale, Maria Rosaria and Z{\"o}ller, Johanna Eva Maria and Jansch, Charline and Janz, Anna and Edenhofer, Frank and Klopocki, Eva and van den Hove, Daniel and Vanmierlo, Tim and Rivero, Olga and Kasri, Nael Nadif and Ziegler, Georg Christoph and Lesch, Klaus-Peter},
  title     = {Generation of induced pluripotent stem cell (iPSC) lines carrying a heterozygous (UKWMPi002-A-1) and null mutant knockout (UKWMPi002-A-2) of Cadherin 13 associated with neurodevelopmental disorders using CRISPR/Cas9},
  series = {Stem Cell Research},
  volume    = {51},
  journal   = {Stem Cell Research},
  doi       = {10.1016/j.scr.2021.102169},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-260331},
  year      = {2021},
  abstract  = {Fibroblasts isolated from a skin biopsy of a healthy 46-year-old female were infected with Sendai virus containing the Yamanaka factors to produce transgene-free human induced pluripotent stem cells (iPSCs). CRISPR/Cas9 was used to generate isogenic cell lines with a gene dose-dependent deficiency of CDH13, a risk gene associated with neurodevelopmental and psychiatric disorders. Thereby, a heterozygous CDH13 knockout (CDH13\(^{+/-}\)) and a CDH13 null mutant (CDH13\(^{-/-}\)) iPSC line was obtained. All three lines showed expression of pluripotency-associated markers, the ability to differentiate into cells of the three germ layers in vitro, and a normal female karyotype.},
  language  = {en}
}
@article{deMunterPavlovGorlovaetal.2021,
  author    = {de Munter, Johannes and Pavlov, Dmitrii and Gorlova, Anna and Sicker, Michael and Proshin, Andrey and Kalueff, Allan V. and Svistunov, Andrey and Kiselev, Daniel and Nedorubov, Andrey and Morozov, Sergey and Umriukhin, Aleksei and Lesch, Klaus-Peter and Strekalova, Tatyana and Schroeter, Careen A.},
  title     = {Increased Oxidative Stress in the Prefrontal Cortex as a Shared Feature of Depressive- and PTSD-Like Syndromes: Effects of a Standardized Herbal Antioxidant},
  series = {Frontiers in Nutrition},
  volume    = {8},
  journal   = {Frontiers in Nutrition},
  issn      = {2296-861X},
  doi       = {10.3389/fnut.2021.661455},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-236326},
  year      = {2021},
  abstract  = {Major depression (MD) and posttraumatic stress disorder (PTSD) share common brain mechanisms and treatment strategies. Nowadays, the dramatically developing COVID-19 situation unavoidably results in stress, psychological trauma, and high incidence of MD and PTSD. Hence, the importance of the development of new treatments for these disorders cannot be overstated. Herbal medicine appears to be an effective and safe treatment with fewer side effects than classic pharmaca and that is affordable in low-income countries. Currently, oxidative stress and neuroinflammation attract increasing attention as important mechanisms of MD and PTSD. We investigated the effects of a standardized herbal cocktail (SHC), an extract of clove, bell pepper, basil, pomegranate, nettle, and other plants, that was designed as an antioxidant treatment in mouse models of MD and PTSD. In the MD model of "emotional" ultrasound stress (US), mice were subjected to ultrasound frequencies of 16-20 kHz, mimicking rodent sounds of anxiety/despair and "neutral" frequencies of 25-45 kHz, for three weeks and concomitantly treated with SHC. US-exposed mice showed elevated concentrations of oxidative stress markers malondialdehyde and protein carbonyl, increased gene and protein expression of pro-inflammatory cytokines interleukin (IL)-1β and IL-6 and other molecular changes in the prefrontal cortex as well as weight loss, helplessness, anxiety-like behavior, and neophobia that were ameliorated by the SHC treatment. In the PTSD model of the modified forced swim test (modFST), in which a 2-day swim is followed by an additional swim on day 5, mice were pretreated with SHC for 16 days. Increases in the floating behavior and oxidative stress markers malondialdehyde and protein carbonyl in the prefrontal cortex of modFST-mice were prevented by the administration of SHC. Chromatography mass spectrometry revealed bioactive constituents of SHC, including D-ribofuranose, beta-D-lactose, malic, glyceric, and citric acids that can modulate oxidative stress, immunity, and gut and microbiome functions and, thus, are likely to be active antistress elements underlying the beneficial effects of SHC. Significant correlations of malondialdehyde concentration in the prefrontal cortex with altered measures of behavioral despair and anxiety-like behavior suggest that the accumulation of oxidative stress markers are a common biological feature of MD and PTSD that can be equally effectively targeted therapeutically with antioxidant therapy, such as the SHC investigated here.},
  language  = {en}
}
@article{ZieglerRadtkeVitaleetal.2021,
  author    = {Ziegler, Georg C. and Radtke, Franziska and Vitale, Maria Rosaria and Preuße, Andr{\´e} and Klopocki, Eva and Herms, Stefan and Lesch, Klaus-Peter},
  title     = {Generation of multiple human iPSC lines from peripheral blood mononuclear cells of two SLC2A3 deletion and two SLC2A3 duplication carriers},
  series = {Stem Cell Research},
  volume    = {56},
  journal   = {Stem Cell Research},
  doi       = {10.1016/j.scr.2021.102526},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-264696},
  year      = {2021},
  abstract  = {Copy number variants of SLC2A3, which encodes the glucose transporter GLUT3, are associated with several neuropsychiatric and cardiac diseases. Here, we report the successful reprogramming of peripheral blood mononuclear cells from two SLC2A3 duplication and two SLC2A3 deletion carriers and subsequent generation of two transgene-free iPSC clones per donor by Sendai viral transduction. All eight clones represent bona fide hiPSCs with high expression of pluripotency genes, ability to differentiate into cells of all three germ layers and normal karyotype. The generated cell lines will be helpful to enlighten the role of glucometabolic alterations in pathophysiological processes shared across organ boundaries.},
  language  = {en}
}
@article{PrelogHilligardtSchmidtetal.2016,
  author    = {Prelog, Martina and Hilligardt, Deborah and Schmidt, Christian A. and Przybylski, Grzegorz K. and Leierer, Johannes and Almanzar, Giovanni and El Hajj, Nady and Lesch, Klaus-Peter and Arolt, Volker and Zwanzger, Peter and Haaf, Thomas and Domschke, Katharina},
  title     = {Hypermethylation of FOXP3 Promoter and Premature Aging of the Immune System in Female Patients with Panic Disorder?},
  series = {PLoS ONE},
  volume    = {11},
  journal   = {PLoS ONE},
  number    = {6},
  doi       = {10.1371/journal.pone.0157930},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-179684},
  year      = {2016},
  abstract  = {Immunological abnormalities associated with pathological conditions, such as higher infection rates, inflammatory diseases, cancer or cardiovascular events are common in patients with panic disorder. In the present study, T cell receptor excision circles (TRECs), Forkhead-Box-Protein P3 gene (FOXP3) methylation of regulatory T cells (Tregs) and relative telomere lengths (RTLs) were investigated in a total and subsamples of 131 patients with panic disorder as compared to 131 age- and sex-matched healthy controls in order to test for a potential dysfunction and premature aging of the immune system in anxiety disorders. Significantly lower TRECs (p = 0.004) as well as significant hypermethylation of the FOXP3 promoter region (p = 0.005) were observed in female (but not in male) patients with panic disorder as compared to healthy controls. No difference in relative telomere length was discerned between patients and controls, but significantly shorter telomeres in females, smokers and older persons within the patient group. The presently observed reduced TRECs in panic disorder patients and FOXP3 hypermethylation in female patients with panic disorder potentially reflect impaired thymus and immunosuppressive Treg function, which might partly account for the known increased morbidity and mortality of anxiety disorders conferred by e.g. cancer and cardiovascular disorders.},
  language  = {en}
}
@article{FernandezCastilloCabanaDominguezKappeletal.2021,
  author    = {Fern{\`a}ndez-Castillo, No{\`e}lia and Cabana-Dom{\´i}nguez, Judit and Kappel, Djenifer B. and Torrico, B{\`a}rbara and Weber, Heike and Lesch, Klaus-Peter and Lao, Oscar and Reif, Andreas and Cormand, Bru},
  title     = {Exploring the contribution to ADHD of genes involved in Mendelian disorders presenting with hyperactivity and/or inattention},
  series = {Genes},
  volume    = {13},
  journal   = {Genes},
  number    = {1},
  issn      = {2073-4425},
  doi       = {10.3390/genes13010093},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-252346},
  year      = {2021},
  abstract  = {Attention-deficit hyperactivity disorder (ADHD) is a complex neurodevelopmental disorder characterized by hyperactivity, impulsivity, and/or inattention, which are symptoms also observed in many rare genetic disorders. We searched for genes involved in Mendelian disorders presenting with ADHD symptoms in the Online Mendelian Inheritance in Man (OMIM) database, to curate a list of new candidate risk genes for ADHD. We explored the enrichment of functions and pathways in this gene list, and tested whether rare or common variants in these genes are associated with ADHD or with its comorbidities. We identified 139 genes, causal for 137 rare disorders, mainly related to neurodevelopmental and brain function. Most of these Mendelian disorders also present with other psychiatric traits that are often comorbid with ADHD. Using whole exome sequencing (WES) data from 668 ADHD cases, we found rare variants associated with the dimension of the severity of inattention symptoms in three genes: KIF11, WAC, and CRBN. Then, we focused on common variants and identified six genes associated with ADHD (in 19,099 cases and 34,194 controls): MANBA, UQCC2, HIVEP2, FOPX1, KANSL1, and AUH. Furthermore, HIVEP2, FOXP1, and KANSL1 were nominally associated with autism spectrum disorder (ASD) (18,382 cases and 27,969 controls), as well as HIVEP2 with anxiety (7016 cases and 14,475 controls), and FOXP1 with aggression (18,988 individuals), which is in line with the symptomatology of the rare disorders they are responsible for. In conclusion, inspecting Mendelian disorders and the genes responsible for them constitutes a valuable approach for identifying new risk genes and the mechanisms of complex disorders.},
  language  = {en}
}